Biotehniška fakulteta Univerze v Ljubljani Biotechnical Faculty University of Ljubljana Acta agriculturae Slovenica • ISSN 1581-9175 • 99 - 2 • Ljubljana, september 2012 Acta agriculturae Slovenica Volume / Letnik 99 • Number / Številka 2 • 2012 VSEBINA / CONTENTS Sali ALIU, Imer RUSINOVCI, Shukri FETAHU, and Emilija SIMEONOVSKA 121 Genetic diversity and correlation estimates for grain yield and quality traits in Kosovo local maize (Zea mays L.) populations Genetska raznolikost in korelacije med pridelkom zrnja in kakovostnimi lastnostmi zrnja lokalnih populacij koruze (Zea mays L.) na Kosovem Pakeza DRKENDA, Amna SPAHIC, Ajla SPAHIC, Asima BEGIC-AKAGIC 129 Testing of 'Gisela 5' and 'Santa Lucia 64' cherry rootstocks in Bosnia and Herzegovina Preizkušanje češnjevih podlag 'Gisela 5' in 'Santa Lucia 64' v Bosni in Hercegovini SH. LORZADEH, A. MAHDAVIDAMGHANI, M. R. ENAYATGHOLIZADEH and M. YOUSEFI 137 Reasearch of Energy use efficiency for maize production systems in Izeh, Iran Raziskava energetske učinkovitosti pridelave koruze v Izehu, Iran Lidija TOMIC, Nataša ŠTAJNER, Tatjana JOVANOVIC CVETKOVIC, Miljan CVETKOVIC and Branka JAVORNIK 143 Collection and genetic characterization of Vitis vinifera ' Žilavka' by microsatellites and AFLP markers Zbiranje vinske trte sorte Žilavka (Vitis vinifera L.) in genetska karakterizacija z mikrosatelitnimi in AFLP markerj Filip VUČAJNK, Rajko BERNIK 151 Improved quality of fungicide deposition and coverage of potato leaves using flat fan air-injector nozzle IDK Izboljšanje depozicije in pokritosti listov krompirja s škropilno brozgo pri uporabi injektorske špranjaste šobe IDK Vesna ZUPANC1 Reinhard NOLZ, Peter CEPUDER, Branka BRAČIČ - ŽELEZNIK, Marina PINTAR 165 Determination of water balance components with high precision weighing lysimeter in Kleče Določitev členov vodne balance z natančnim tehtalnim lizimetrom v Klečah Seyed Jaber ALAVION, Mohammad Sadegh ALLAHYARI 175 E-readiness of Rural ICT Offices for Rice e-marketing in Rasht Township, Iran Pripravljenost podeželskih IKT svetovalcev za e-marketing riža na območju mesta Rasht, Iran Huda Abdel-karim Al-TAHA, Abbas Mehdi JASIM and Muayed Fadhil ABBAS 185 Somatic embryogenesis and plantlet regeneration from nucleus tissues of Local orange (Citrus sinensis (L.) Osbeck) Somatska embriogeneza in regeneracija iz nucelarnega tkiva lokalne pomaranče (Citrus sinensis (L.) Osbeck) Muhammad SAEED AWAN, Azhar HUSSAIN, Tanveer ABBAS and Rehmat KARIM 191 Assessment of production practices of small scale farm holders of tomato in Bagrote Valley, CKNP region of Gilgit-Baltistan, Pakistan Ocenjevanje pridelovanja paradižnika na majhnih kmetijah v dolini Bagrote, CKNP območje Gilgit-Baltistana, Pakistan Terezija GOLOB, Jasna BERTONCELJ, Mojca KOROŠEC 201 Pomen prehranske vlaknine v prehrani človeka The importance of dietary fibre in human nutrition Primož GRIŽON, Gabrijel SELJAK, Irma VUK 213 Migration of Scaphoideus titanus Ball from the surrounding vineyards into the nursery Migracija ameriškega škržatka (Scaphoideus titanus Ball) iz bližnjih vinogradov v trsnico Žiga LAZNIK, Lea MILEVOJ, Stanislav TRDAN 225 Pisana polonica (Harmonia axyridis [Pallas], Coleoptera, Coccinellidae) - invazivna koristna vrsta Multicoloured asian lady beetle (Harmonia axyridis [Pallas], Coleoptera, Coccinellidae) - invasive beneficial species Andreja SUŠNIK, Ajda VALHER, Gregor GREGORIČ, Marko TROŠT 235 Tools for agricultural drought detection in the frame of Drought Management Centre for Southeastern Europe - DMCSEE Orodja za ugotavljanje kmetijske suše v okviru centra za upravljanje s sušo v JV Evropi - DMCSEE Melita ŠTRUKELJ, Irena MAVRIČ PLEŠKO, Gregor UREK, Stanislav TRDAN 255 Kaparji (Hemiptera: Coccoidea) vinske trte (Vitis vinifera L.) v Sloveniji in možnosti njihovega biotičnega zatiranja Soft scales and mealybugs (Hemiptera: Coccoidea) on grapevine (Vitis vinifera L.) in Slovenia and the possibilities of their biological control Tomaž BARTOL, Karmen STOPAR 271 Content analysis of the papers in the Acta agriculturae Slovenica Vsebinska obdelava prispevkov v Acta agriculturae Slovenica let. 99 št. 2 277 Popravek Corrigendum 279 Navodila avtorjem Notes for authors COBISS Code 1.01 DOI: 10.2478/v10014-012-0011-6 Agrovoc descriptors: zea mays, maize, cereals, land varieties, crop yield, yields, seed, proximate composition, proteins, oils, starch, genotypes, phenotypes, agronomic characters, quality, plant breeding, genetic variation, biological differences, varieties Agris category code: f01, f30 Genetic diversity and correlation estimates for grain yield and quality traits in Kosovo local maize (Zea mays L.) populations Sali ALIU1, Imer RUSINOVCI2, Shukri FETAHU3, and EMILIJA SIMEONOVSKA4 Received May 7, 2012; accepted July 18, 2012. Delo je prispelo 7. maja 2012, sprejeto 18. julija 2012. ABSTRACT The aim of the presented investigation was to estimate the genetic diversity, and correlation analysis among yield and quality traits in twenty local maize populations. The experiment was based on randomized complete block design (RCBD) with three replications. In the study we compared grain yield, and quality traits such as protein, oil and starch content in grain. The results showed that there were significant differences among populations. The overall mean grain yield was 79.33 g plant-1 with the highest grain yield in population GBK-7 (105.13 g plant-1). The protein and oil contents ranged between 11.02 to 13.02% and 2.56 to 5.57%, respectively. The starch content varied from 68.58 to 70.92%. The first two canonical discriminant functions were significant at p < 0.01. It is important to point out the great relevance of the first two discriminant functions justifying 95.80% of the variability among populations. There were also big differences regarding phenotypic correlations. The study suggests that the quality traits are phenotypically and genotypically highly variable and therefore very useful for breeding process Key words: local maize populations, protein, oil, starch IZVLEČEK GENETSKA RAZNOLIKOST IN KORELACIJE MED PRIDELKOM ZRNJA IN KAKOVOSTNIMI LASTNOSTMI ZRNJA LOKALNIH POPULACIJ KORUZE (Zea mays L.) NA KOSOVEM Namen raziskave je bil proučiti genetsko raznolikost in korelacije med pridelkom in nekaterimi kakovostnimi lastnostmi zrnja (vsebnost beljakovin, olja, škroba in pepela v zrnju) 20 lokalnih populacij koruze na Kosovem. Poskus je bil postavljen po metodi naključnih blokov v 3 ponovitvah. Za vse lastnosti so ugotovljene statistično značilne razlike med proučevanimi populacijami. Povprečni pridelek zrnja vseh populacij je znašal 79,33 g rastlino-1, najvišji pridelek je imela populacije GBK-7 (105,13 g rastlino-1). Vsebnost beljakovin se je gibala med 11,02 in 13,02 %, olja med 2,56 in 5,57 % in škroba med 68,58 in 70.92 %. Z diskriminantno analizo je ugotovljeno, da sta prvi dve komponenti pojasnili 95,80 % varabilnosti med populacijami. Med nekaterimi lastnostmi so za proučevane populacije ugotovili signifikantne korelacije. Glede na veliko genetsko variabilnost smatramo, da bi proučevane lokalne populacije lahko bile koristne v nadaljnjem žlahtnjenju genotipov koruze z dobrimi kakovostnimi lastnostmi zrnja. Ključne besede: lokalne populacije koruze, Kosovo, pridelek zrnja, beljakovine, olje, škrob 1 The University of Prishtina, Faculty of Agriculture, Kosovo, Asoc. Prof., e-mail: salialiu02@gmail.com 2 The University of Prishtina, Faculty of Agriculture, Kosovo, Asoc. Prof. 3 The University of Prishtina, Faculty of Agriculture, Kosovo, Prof. 4 The Faculty of Agriculture science and Food, Macedonia, Assistant Prof. Acta agriculturae Slovenica, 99 - 2, september 2012 str. 121 - 128 1 INTRODUCTION Maize (Zea mays L.) is considered to be a major source of food for livestock and humans due to its relatively high content of proteins, oil, starch and some other important vitamins such as vitamin B and B12. Yellow maize can provide a substantial amount of vitamin A, and the maize germ is rich in vitamin E (Okoruwa et al, 1996). The maize crop is considered to be an integral part of Kosovo's agricultural production system and has a potential to compete with other crops. In order to have access to the global market, there is a need to improve the yield quality with judicious use of inputs (Saleem et al, 2008). Maize is commonly used in animal feed as an energy source for its high starch content (Oliveira et al, 2006). Several million people, particularly in developing countries, derive their protein and calorie requirements from maize. Some of the most important traits of interest in the maize market are protein and oil content. The protein content (PC) is a quantitative trait and several studies have pointed out that there is a great number of genes involved in its control (Mittelman et al, 2003). Protein is an expensive but necessary constituent of both food and feed. Grain protein quantity in ordinary maize is relatively low (80-110 g kg-1) and of poor quality because of low levels of amino acids, lysine and tryptophan (Bjarnason and Vasal, 1992). Maize protein which ranges from 6 to 12% is regarded to be inferior because it is low in lysine and tryptophan (FAO, 1988). This may cause nutritional deficiencies when maize is used as an exclusive protein source, without the addition of supplements (Glover and Mertz, 1987). Some proteins in maize have anti-fungal qualities. The basis of resistance to fungal infection may lie with protein content, type, or distribution in the tissue (Guo et al, 1997). The existence of genetic variability and the prospect of selection for protein content in maize have been demonstrated in several studies (Micu et al., 1995). Most of the oil is in the germ of the kernel. Oil and protein contents have been increased to levels almost twice as high as those of the original grain (Jugenheimer, 1961). High-oil corn (HOC) inbreds were first developed in 1896 and some hybrids containing 6-8% oil (Haumann, 1996), and affected by the size of embryo, maturity, and position of the kernel on the ear (Lambert 2001). Breeding studies in maize to enhance fatty acid composition started in 1970's; however, they have not continued. Research in this area dealt with different aspects of grain quality, focusing mainly on determination of the grain quality traits and characterization of maize genotypes in terms of fatty acid composition (Egesel et al, 2011). The major use of HOC is in livestock feed because of its higher metabolizable energy value (Weber, 1987). The developing countries have more areas dedicated to maize cultivation than developed countries, but yield in the latter is about four times higher. While most production in developing countries is used for human consumption, in developed world, it is mainly used for animal feed and industry (FAO, 1988). As indicated earlier, maize has three possible uses such as food, feed for livestock and raw material for industry. Maize is one of the most important grain crops in Kosovo, with over 60,000 hectares in production (MAFRD, 2010) where the area under local maize populations is more than 5%. In most cases, the cultivation of local populations is associated with their adaptability to specific environments and with their nutritional value. It is frequently used for human consumption as corn bread that can be consumed together with milk. The main objective of the present study was to populations and to identify the quality traits describe and analyze twenty local maize with more differentiating ability. 2 MATERIAL AND METHODS Plant material and experimental design: Twenty local maize populations (LMP), collected from different regions of Kosovo, were used in this study (Table 1). The experiment was carried out in a randomized complete block design with three replicates in Prishtina 42°38'29.76" N and 21° 07'16.49" E on 571 m of altitude in 2010. The climate of the region is semiarid with hot summers. The soil in the experimental area is classified as vertisol (black soil). Standard agronomic practices were used to provide adequate nutrition and keep the plots disease free. Each plot consisted of a row 5 m long with an inter and intra row plant spacing of 0.75 x 0.25 m, resulting in a population density of 53,000 plants ha-1. Area of individual plots in each replication was 15 m2. Table 1. Geographical data of collected Kosovo local maize populations Populations Geographical origin Longitude Latitude Elevation GBK-1 Drenas 020°44'43" 42°41'50" 567 GBK-2 Malisheve 020°44'09" 42°28'12" 562 GBK-3 Malisheve 020°43'22" 42°27'56" 576 GBK-4 Drenas 020°45'53" 42°41'35" 694 GBK-5 Prishtine 021°04'00" 42°35'05" 810 GBK-6 Kamenice 021°31'32" 42°34'16" 766 GBK-7 Kamenice 021°25'32" 42°33'56" 812 GBK-8 Lipjan 021°07'20" 42°31'45" 551 GBK-9 Podujeve 021°12'12" 42°33'39" 598 GBK-10 Drenas 020°54'06" 42°34'50" 585 GBK-11 Vushtrri 021°59'26" 42°50'46" 557 GBK-12 Ferizaj 021°09'39" 42°22'15" 580 GBK-13 Suhareke 020°49'02" 42°21'45" 388 GBK-14 Vushtrri 020°58'30" 42°33'38" 518 GBK-15 Drenas 020°42'32" 42°39'21" 586 GBK-16 Drenas 020°42'46" 42°39'30" 565 GBK-17 Skenderaj 020°48'23" 42°45'00" 623 GBK-18 Skenderaj 020°47'39" 42°44'39" 597 GBK-19 Skenderaj 020°48'04" 42°44'39" 603 GBK-20 Shtime 020°07'06" 42°44'40" 610 Laboratory studies: At harvest time, five random ears were selected from each plot, resulting in a total of 15 ears per individual population. Grains were carefully removed by hand. From each population, an equal number of grains was taken from each plot, mixed together in order to form a balanced sample and then subjected to analyses in the laboratory. The grains obtained were grounded to form a fine powder. The chemical analyses included protein content (PC), starch content (SC) and oil content (OC). Analyses were based on standard methods: PC was determined by the Kjeldahl, while OC was determined by extraction using Soxhlet method (using petroleum ether at boiling point 40-60 °C). Ash content of each sample was determined by drying samples at 550 °C. Statistical analyses: All statistical analyses were performed with the SPSS software (version 15.0, SPSS Inc., 2006). Mean values and variation coefficients were used in the statistical analyses. Effects of the studied traits were evaluated by ANOVA. In order to asses the differentiation of local maize populations (LMP's) based on all variables that were measured, the Canonical Discriminant Analyses (CDA) was applied. CDA is a technique for classifying a set of observation into predefined classes. Relationship among different variables of the quality analyses were tested by Pearson's correlation test. 3 RESULTS AND DISCUSSION Significant differences among the LMP's for grain yield and grain quality such as content of oil, protein, starch, ash and moisture were determined (Table. 2). Table 2: Mean squares for grain yield and quality parameters of 20 Kosovo local maize populations Yield per Oil Protein Starch Sources of plant Content Content Content variation d.f. (g) (%) (%) (%) LMP's 19 2.895 ** 2.863 ** 18.593 ** 4.584 CV% 18.26 13.37 4.40 1.49 Error 38 217.46 0.0019 0.0437 0.728 Ash Content (%) Moisture Content (%) 2.863 3.10 0.0019 247.49 ** 3.62 0.003 ** Significant at p = 0.01. The analysis of variance (ANOVA) showed that the LMP's differed in most characteristics (Table 3). Mean values of all measured characteristics are presented in Table 3. The mean values of the grain yield per plant at LMP's were 79.33 g plant-1. It is evident from our results that local maize population GBK-7 had maximum grain yield per plant (105.13 g plant-1) which is 25.8 g plant-1 or 32.52% higher than the mean values , whereas LMP's for GBK-13 had the lowest grain yield (59.62 g plant-1) which is 19.71 g plant-1 or 24. 84% lower than the mean value (79.33 g plant-1). High oil content maize is a special type that has been bred to have higher percent oil content (OC) than regular yellow maize. Typically, oil content of yellow maize varies from 3.5 to 4%. Ideally, high oil content maize should contain from 7 to 8% of oil (Heiniger, 1997). Kernel oil content is considered to be a quantitative trait controlled by numerous genes with small effects (Dudley, 1977). The data showed a relatively wide range among the LMP's for OC. The overall mean value for the OC was 4.44%. The genotype GBK-5 exhibited maximum OC value with 5.57%, while GBK-13 had the lowest OC value (2.56%). Different range of variation (5.26 and 7.17%) was observed by Berardo et al, (2009). Has et al., (2009) reported different values which varied from 0.04 to 12.3%. Significant values of OC were also reported by Saleem et al. (2008). Table 3: Mean values of grain yield and quality characters in Kosovo local maize populations Local maize Ash content Oil content Moisture Protein Starch Yield populations (%) (%) content (%) content (%) content (%) (plant-1g) GBK-1 1.44±0.020 4.37±0.032 14.48±0.030 13.02±0.215 68.58±0.535 69.69±1.060 GBK-2 1.38±0.028 4.53±0.316 14.14±0.040 11.69±0.049 69.87±0.640 88.97±9.763 GBK-3 1.33±0.080 3.83±0.520 14.56±0.005 12.50±0.205 70.70±0.362 102.55±7.230 GBK-4 1.38±0.025 4.01±0.198 14.84±0.085 11.75±0.280 70.96±0.753 93.30±5.863 GBK-5 1.39±0.055 5.57±0.456 14.16±0.045 11.59±0.176 69.97±0.761 86.29±14.657 GBK-6 1.34±0.051 4.30±0.445 14.85±0.020 11.72±0.200 70.19±0.223 82.08±21.328 GBK-7 1.34±0.035 4.78±0.413 14.14±0.040 11.32±0.202 70.43±0.355 105.13±11.017 GBK-8 1.28±0.045 4.31±0.518 14.50±0.078 11.05 ±0.435 72.15±1.162 82.43±4.787 GBK-9 1.35±0.015 4.49±0.181 14.67±0.075 11.02 ±0.258 70.02±0.920 99.86±8.741 GBK-10 1.35±0.032 4.27±0.208 14.45±0.005 11.64±0.081 70.23±0.309 78.34±17.001 GBK-11 1.34±0.043 4.37±0.457 14.56±0.046 11.59±0.134 70.92±0.453 69.83±17.969 GBK-12 1.31±0.052 4.40±0.705 14.07±0.015 11.15±0.223 70.68±0.850 75.77±17.339 GBK-13 1.36±0.030 2.56±0.181 16.42±0.111 11.99±0.161 70.36±0.420 59.62±16.243 GBK-14 1.36±0.023 4.66±0.408 14.61±0.077 11.92±0.217 70.34±1.125 78.43±3.458 GBK-15 1.45±0.070 4.44±0.866 14.19±0.043 12.49±0.308 68.63±1.341 85.47±16.479 GBK-16 1.43±0.032 4.89±0.394 14.24±0.062 12.52±0.070 67.39±0.747 67.36±29.061 GBK-17 1.38±0.026 4.67±0.050 14.01±0.075 11.86±0.160 69.41±0.660 72.67±15.445 GBK-18 1.36±0.060 5.25±0.728 14.10±0.010 11.67±0.081 69.33±1.236 67.21±14.839 GBK-19 1.37±0.023 4.85±0.496 14.63±0.026 12.11±0.209 69.24±1.400 74.39±18.798 GBK-20 1.41±0.047 4.34±0.699 14.18±0.095 11.60±0.081 70.40±1.013 47.33±10.565 Mean 1.36 4.44 14.48 11.81 69.90 79.33 CV % 3.10 13.37 3.62 4.40 1.49 18.26 The variation for protein content (PC) was found to be higher than the variation for OC. The ANOVA indicated that the differences among the LPM's for PC were highly significant (Table 3). The mean value of PC observed in the present study was 11.81%. Some of LMP's were identified with high grain PC ranging from 11.02 to 13.02%. This can be regarded as a relatively high level of PC. The LMP's also showed a high genetic variation (16.93%). The variation for the protein content has been well demonstrated by numerous studies. Has et al, (2009) at some LMP's reported variation from 11.2 to 15.6%; while Prasanna et al, (2001) presented different results which varied from 8.9 to 10.2%. From the data shown in Table 3 it is evident that the starch content (SC) of maize kernels depends to a very large extent on genotype of population. The starch content (SC) ranging between 67.39 and 72.15%, while the grand mean values of SC was 69.90%. There were significant differences at p = 0.01. Similar results (58.1 to 72%) for SC in different LMP were reported by Has et al., (2009). Also ash content (AC) ranged from 1.28 to 1.45%. Table 4: Summary statistics for canonical discriminant standardized functions Discriminant functions 1 2 3 4 5 6 Eigenvalue 179.22 12.26 5.24 1.72 1.14 0.29 Percentage of variation 89.70 6.10 2.60 0.90 0.60 0.10 Cumulative percentage 89.70 95.80 98.40 99.30 99.90 100.00 Canonical correlation 0.99 0.96 0.91 0.79 0.73 0.47 Wilks' Lambda 0.00 0.002 0.021 0.132 0.360 0.771 Chi-square 535.17 296.24 177.31 93.04 46.98 11.97 df 114 90 68 48 30 14 Significance <0.001 <0.001 <0.001 <0.001 0.025 0.608 Elements of Structure Matrix Ash Content (%) 0.003 0.291 -0.065 -0.209 -0.029 0.931 * Oil Content (%) -0.095 -0.005 0.133 -0.431 -0.145 0.876 * Moisture (%) 0.789 * -0.549 0.261 -0.019 -0.070 0.042 Protein Content (%) 0.053 0.752 * 0.503 -0.135 -0.188 -0.354 Starch Content (%) 0.015 -0.296 -0.004 0.685 * 0.471 -0.470 Grain yield (%) -0.019 -0.082 0.092 0.506 -0.800 * 0.296 * Largest absolute correlation between each variable and any discriminant function In table 4 the canonical discriminant functions discriminant functions justifying 95.80% of are described, the eigenvalue, percentages of the variability. The first discriminant function variation of each function and the cumulative showed a significant positive correlation with variance of the six discriminant functions. the moisture (0.789) following by protein and Table presents as wdl the standardized starch content (0.053 and 0.015). But, the elements of structure matrix. The first two negative correlation (-0.019) was determined canonical discriminant functions were between first descriminant function and grain significant at p < 0.01. It is important to point yiled (Table 5). out the great relevance of the first two Table 5: Pearson's correlations between yield and grain quality traits Oil Protein Starch Ash Trait Yield Content Content content Content (%) (%) (%) (%) Oil Content (%) 0.12 Protein Content (%) -0.19 -0.12 Starch Content (%) 0.33 * -0.15 -0.68 * Ash Content (%) -0.30 * 0.17 0.69 * -0.58 * Moisture Content (%) -0.15 -0.80 ** 0.09 0.14 -0.15 * = significant at p = 0.05. and p = 0.01 Maize breeders expect that kernel protein and oil content should be negatively correlated with plant yield. In our study, grain yield per plant was positively and significantly correlated with starch content (r = 0.33*), positively and nonsignificantly correlated with oil content (r = 0.12) and was negatively correlated with protein content (r = -0.19). Also, the significant correlation was obtained between Ash content (AC) and protein content (PC) on value 0.69. Table 5. The possible cause for observed correlation was probably due to reduction of starch content in the grains. The presented results are in partial agreement et al., (2008). with the results of Has et al, (2009) and Salem Canonical Discriminant Functions 15 □ 16° P ° 20 3 ■J7" "3 -J5 -rt6 O 13 * O 7 9 0 ■ 8 □ O 20 Function 1 VAR00001 01 02 C>3 04 O 5 O6 O 7 O 8 05 O 10 011 O 12 O 13 O 14 O 15 O 16 O 17 O20 I I Group Centroid Figure 1: Canonical discriminant analyses of local maize populations by grain yield and quality characteristics applied (4 - 7 mismatches allowed at the 3' end of primers). The canonical discriminant analysis of the traits is presented in Figure 1. The first canonical functions described 89.7% and a second canonical function is 6.1% of the existing variance. Ash content had the strongest influence in the Function 1, while the Functions 2 was mostly influenced by the oil content followed by protein content and starch content. 6 3- 0 0 40 4 CONCLUSIONS The study showed that there was a significant genetic variability for many traits among local maize populations. High variability was determined for PC, OC and SC. Positive and significant correlations were found between yield and starch contents. Negative correlation was found between yield and protein content. The first canonical function described 89.7% and a second canonical function is 6.1% of the existing variance. The investigated maize populations could be considered as a source of new genetic variability, and could be successfully used for the development of maize inbred lines in the Kosovo breeding program. 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Current Science, 81: (10), 1308-1319. Saleem, M., Ahsan, M., Salam, M., Majeed, A. 2008. Comparative evaluation and correlation estimates for grain yield and quality attributes in maize. Pak. J. Bot. 40: (6), 2361-2367. SPSS-16. 2006. Statistical package programme. Weber, E. 1987. Lipids of the kernel in corn. Chemistry and Technology, 311-349. COBISS Code 1.01 DOI: 10.2478/v10014-012-0012-5 Agrovoc descriptors: prunus avium, cherries, fruit crops, stone fruits, varieties, land varieties, fruits, quality, rootstocks, orchards, fruit growing, flowering, growth, plant developmental stages, biological development, proximate composition, plant breeding, climatic factors, adaptation Agris category code: f60, f62 Testing of 'Gisela 5' and 'Santa Lucia 64' cherry rootstocks in Bosnia and Herzegovina Pakeza DRKENDA1, Amna SPAHIC2, Ajla SPAHIC2, Asima BEGIC-AKAGIC3 Received July 04, 2012; accepted August 21, 2012. Delo je prispelo 04. julija 2012, sprejeto 21. avgusta 2012. ABSTRACT IZVLEČEK Cherry cultivation has a long tradition in Bosnia and Herzegovina mainly due to favorable climatic conditions for cherry growing in this region. However, current cherry production is insufficient because of prevailing old cultivars and rootstocks. Modern intensive production of sweet cherry (Prunus avium L.) requires planting of high quality cultivars on dwarfing rootstocks planted in high density orchards. Cherry rootstock breeding programs worldwide require data on tolerance and performance of their rootstocks in different climatic conditions. Therefore, the influence of two cherry rootstocks ('Gisela 5 and 'Santa Lucia 64') on phenological events (blooming), growth and pomological properties of two cherry cultivars ('Stella' and 'Burlat') planted in modern orchard (managed according to standard commercial practice for integrated fruit production), near Sarajevo was evaluated. The trees grafted on 'Gisela 5' rootstocks were planted in 2004 and on 'Santa Lucia 64' in 2005. All tress were trained in a spindle system and the analyzed parameters were monitored in 2010. Rootstocks greatly influenced blooming time, growth and fruit characteristics of both investigated cultivars. The weaker rootstock was 'Gisela 5', which stimulated earlier blooming and caused statistically significant better fruit characteristics (fruit size, % flesh of fruit as well as total soluble solids content in fruit). The results of the analysis showed that both cherry cultivars reached better fruit quality on 'Gisela 5'. 'Stella' had better fruit quality than 'Burlat'. 'Santa Lucia 64' proved a better rootstock for 'Burlat' than for 'Stella'. Key words: cherry, cultivar, dwarfing rootstocks, trunk cross section area (TCSA), 'Stella', 'Burlat', 'Gisela 5', 'Santa Lucia 64' PREIZKUŠANJE CESNJEVIH PODLAG GISELA 5' IN SANTA LUCIA 64' V BOSNI IN HERCEGOVINI Gojenje češenj v Bosni in Hercegovini ima dolgo tradicijo. Glavni razlog so ugodne klimatske razmere za gojenje češenj. Vendar pa je trenutna pridelava češenj premajhna zaradi starih sort in njihovih podlag. Sodobna intenzivna pridelava češenj (Prunus avium L.) zahteva sajenje visokokakovostnih sort na šibkih podlagah v nasadih z gostim sajenjem. Programi vzgoje novih češnjevih podlag po svetu potrebujejo podatke o odpornosti in obnašanju podlag v različnih klimatskih razmerah. Ugotavljali smo vpliv dveh češnjevih podlag ('Gisela 5' in 'Santa Lucia 64') na fenološke lastnosti (cvetenje), rast in pomološke lastnosti dveh češnjevih sort ('Stella' in 'Burlat'), ki sta bili posajeni v sodobnem nasadu blizu Sarajeva, oskrbovanem po načelih integrirane pridelave. Drevesa na podlagi 'Gisela 5' so bila posajena leta 2004 in na podlagi 'Santa Lucia 64' leta 2005. Drevesa smo opazovali v letu 2010, vzgojena so bila v gojitveni obliki vretenast grm. Podlagi sta značilno vplivali na cvetenje, rast in na značilnosti plodov pri obeh obravnavanih sortah. Šibkejša podlaga je bila 'Gisela 5', kjer je bilo cvetenje zgodnejše in plodovi so imeli boljše značilnosti (velikost ploda, delež mesa kakor tudi vsebnost suhe snovi v plodu). Analiza je pokazala, da sta obe češnjevi sorti razvili bolj kakovostne plodove na podlagi 'Gisela 5'. Sorta 'Stella' je imela kakovostnejše plodove kot sorta 'Burlat'. Za sorto 'Burlat' je podlaga 'Santa Lucia 64' bolj primerna kot za sorto 'Stella'. Ključne besede: češnja, sorta, šibke podlage, ploščina preseka debla, 'Stella', 'Burlat', 'Gisela 5', 'Santa Lucia 64' 1 University Sarajevo, Faculty of Agricultural and Food Sciences, Department of Fruit and Viticulture Growing, pakeza@bih.net.ba 2 University Sarajevo, Faculty of Agricultural and Food Sciences, Student of Master Stady Programm Fruit Growing University Sarajevo, Faculty of Agricultural and Food Sciences, Department Food Processing 1 INTRODUCTION Cherry growing has a long tradition in Bosnia and Herzegovina. However, the current sweet cherry production is quite small. In recent years the government and research institutions have made efforts to improve cherry production in the region. Now, the producers can get more information concerning modern systems of cultivation, recent cherry cultivars, rootstocks, etc. Modern, high-productive cherry cultivars, which require the application of appropriate agrotechnical practices in order to achieve high yields with a good fruit quality, were introduced in cherry production in Bosnia and Herzegovina in the past years. In addition to planting new cultivars, new rootstocks must also be introduced as they are essential for high density cherry planting. The proper choice of rootstock is one of the key factors for successful cherry production. The rootstock has a direct impact on nutrition, vegetative growth, longevity, yield, fruit quality and resistance of fruit trees (Usenik et al., 2010a). In Bosnia and Herzegovina, the cherry was traditionally grafted on generative rootstocks (Prunus avium and Prunus mahaleb), which are characterized by strong vigor resulting in higher harvesting costs. Cherry rootstock breeding programs worldwide collect data on rootstocks tolerance to different soil properties as well as select rootstocks for "high density" orchard design and early production (Callesen, 1998; Sansavini et al., 1994, Sansavini and Lugly, 1998). For achieving lower tree vigor it is important to select fertile land and to apply all agro-pomotechnical measures for intensive cherry production (Riesen and Ladner, 1998). Adaptation to regional climates and soil condition is also an important criterion during the evaluation of cherry rootstocks. Big differences can exist in the vigor habits and yield of trees even between areas in close vicinity (Siegleri et al., 2000). The choice of rootstock influences the growth, precocity, blooming date, yield and fruit quality (Beckman et al., 1992; Sugar et al., 1999). Therefore, new dwarfing and semi-dwarfing rootstock for cherry must reduce vigor, be graft compatible and site adaptable, and should have good fruit quality without reduction in fruit size and quality (Reighard et al., 2006). The aim of this study was to evaluate two cherry cultivars grafted on two rootstocks in the ecological conditions of Bosnia and Herzegovina. 2 MATERIALS AND METHODS The cherry cultivars 'Stella' and 'Burlat' were grafted on two rootstocks: 'Gisela 5' and 'Santa Lucia 64'. Evaluation was carried out in the cherry orchard located in Podlugovi - Ilijas municipality, nearby Sarajevo. The parameters were monitored from February to June 2010. The trees grafted on 'Gisela 5' rootstocks were planted in 2004 at a spacing of 4.0 m x 3.0 m and the trees grafted on rootstock 'Santa Lucia 64' were planted in 2005 at a spacing of 4.0 m x 3.5 m. All tress were trained to a spindle. The experiment was arranged as a random design with five trees in 2 replications (10 trees per rootstock). The orchard was managed according to standard commercial practice for integrated fruit production. According to its textural classification, the soil was classified as medium heavy to heavy. The phenological properties (swelling buds, first bloom, full bloom, bloom end) were monitored according to Winter (2002). Trunk circumference was measured 20 cm above the graft union and the data were used for calculation of the trunk cross section area (TCSA). Flower index (FI) was calculated as a number of flower buds in relation to the number of buds. Titratable acids were measured with Titrino 719 S (Metrohm) and expressed as % of malic acid. All quantitative parameters were analyzed statistically and the values obtained in terms of further evaluation were tested by mathematical - statistical tests (using one-way analysis of variance - ANOVA test) at p<0.05. 3 RESULTS AND DISCUSSION Phenological observations are presented in Table 1. Table 1: Flowering phenology of 'Stella' and 'Burlat' cherry cultivars grafted on two rootstocks Phenophase 'Stella'/ 'Gisela 5' 'Burlat'/ 'Gisela 5' 'Stella'/ 'Santa Lucia 64' 'Burlat'/ 'Santa Lucia 64' Swelling buds 27. 3. 2010 27. 3. 2010 29. 3. 2010 30. 3. 2010 Green cluster 30. 3. 2010 1. 4. 2010 31. 3. 2010 2. 4. 2010 White bud 5. 4. 2010 6. 4. 2010 07. 4. 2010 8. 4. 2010 First bloom 7. 4. 2010 9. 4. 2010 09. 4. 2010 10. 4. 2010 Full bloom 12. 4. 2010 15. 4. 2010 13. 4. 2010 16. 4. 2010 Bloom end 19. 4. 2010 22. 4. 2010 21. 4. 2010 23. 4. 2010 Flowering duration (days) 12 13 12 13 The flowering is a very important parameter affecting cherry productivity. This is a variable quantity, strongly dependent on genetic characteristics of the cultivar and growing conditions during the flowering. Stancevic (1984) researched phenology data of 48 cherry cultivars and reported that flowering duration for cherry is 11-17 days. According to Pirnat et al. (1980) the flowering period of cherry is 12 days. The results of our study showed 12 days flowering duration in 'Stella' and 13 days in 'Burlat'. It can be concluded that 'Stella' and 'Burlat' are sufficiently overlapped in the duration of flowering. This information is important for pollination, because 'Burlat' is a self - sterile cultivar. Usenik and Stampar (2011) reported that 'Burlat' had earlier first bloom (4th April) and longer flowering duration (15 days). The pomological characteristics of analyzed cherry fruits are presented in Table 2. The average fruit weight ranged from 4.30 g to 6.69 g; the highest average fruit weight of both analyzed cultivars (6.69 g and 6.49 g) was measured on 'Santa Lucia 64' rootstock. However, cultivars grafted on 'Gisela 5' developed fruit with significantly higher fruit weight, than those grafted on 'Santa Lucia 64' rootstock. Table 2: Average value of pomological characteristics of 'Stella' and 'Burlat' cherry cultivars grafted on two rootstocksa Fruit Fruit weight Fruit height Fruit width diameter Stone weight % flesh of Cultivar Rootstock (g) (cm) (cm) (cm) (g) fruit Gisela 5 4.3±0.80 a 2.1±0.08 a 2.32±0.2 a 2.03±0.1 a 0.47±0.7 a 92.5±1.3 a 'Stella' Santa Lucia 64 6.49±0.6 b 1.79±0.1 b 1.94±0.5 b 1.61±0.6 b 0.37±0.7 b 91.3±1.4 b Average 5.35±1.3 a 1.94±0.2 a 2.13±0.4 a 1.82±0.3 a 0.42±0.9 a 91.9±1.2 a Gisela 5 4.45±0.5 a 2.1±0.09 a 2.33±0.8 a 1.88±0.7 b 0.43±0.7 a 93.5±1.2 a 'Burlat' Santa Lucia 64 6.69±0.7 b 1.79±0.1 b 1.94±0.8 b 1.63±0.8 b 0.4±0.08 a 90.8±2.3 b Average 5.57±1.3 a 1.94±0.2 a 2.13±0.4 a 1.76±0.5 b 0.42±0.7 a 92.2±2.8 a Average of 'Gisela 5' 6.54±0.7 a 6.54±0.7 a 2.1±0.08 a 2.32±0.1 a 1.96±0.1 a 0.45±0.7 a Average of 'Santa Lucia 64' 4.38±0.7 b 4.38±0.7 b 1.79±0.2 b 1.94±0.7 b 1.62±0.7 b 0.39±0.8 b Cultivar x Rootstock NS NS NS *** * * a Average values ± standard error are presented. Different letters in columns indicate significantly different values at p < 0.05; NS - no significant influence; * - indicate significant influence at p < 0.001; * -indicate significant influence atp < 0.05. Both evaluated cherry cultivars had an equal average fruit height (Table 2). On the other hand, a significantly higher fruit height (2.1 cm) was measured in cultivars grafted on the 'Gisela 5' rootstock compared to those grafted on 'Santa Lucia 64' (1.79 cm). Similar differences between the cultivars were detected in fruit width with the widest fruit determined in 'Burlat' grafted on the 'Gisela 5' rootstock (2.33 cm). The minimum average fruit width was measured on cultivars grafted on the 'Santa Lucia 64' rootstock (1.94 cm). Analysis of variance revealed that only the rootstock had a significant effect on the expression of fruit size (weigh, height and width). For all three analyzed fruit size parameters, the fruits from trees grafted on 'Gisela 5' rootstock had significantly higher mean values compared to fruit from trees grafted on 'Santa Lucia 64'. Similarly, pruning, which indirectly reduces the number of fruiting spurs, also results in increased fruit size and fruit weight (Usenik et al., 2008), but it also reduces total yield (Andersen et al., 1999; Lang, 2001; Kappel, 2002; Whiting and Lang, 2004). As 'Gisela 5' significantly alters the growth potential of cherry cultivars it also positively affects the external fruit quality characteristics. Fruit weight of both cultivars was somewhat lower in relation to the results of other studies. Aliman (2008) stated that the average weight of 'Burlat' was 5.98 g and of 'Stella' 7.67 g. Albertini and Della Strada (1996) reported that the fruit weight of 'Burlat' was 6.65 g. Albertini and Della Strada (1996) reported the average fruit height of 'Stella' fruit below 2.32 cm, and Aliman (2008) measured fruit height of this cultivar in the range of 2.33 cm. Radicevic et al. (2011) reported that the average fruit height of the 'Burlat' was 2.23 cm and Aliman (2008) measured 2.10 cm fruit height in this cultivar. Aliman (2008) reported higher fruit width for 'Stella' (2.47 cm) and 'Burlat' (2.34 cm), while Albertini and Della Strada (1996) reported slightly lower average fruit width for 'Stella' (2.38 cm). Radicevic et al. (2011) reported an average fruit width of 2.43 cm for 'Burlat'. The average fruit diameter of 'Stella' grafted on the 'Santa Lucia 64' rootstock was smaller (1.61 cm) compared to 'Burlat' grafted on the same rootstock (1.63 cm). Cultivar and rootstock, as well as their interactions, exhibited statistically significant influences on fruit diameter. 'Stella' had a significantly higher fruit diameter in relation to 'Burlat'. The fruits from trees grafted on 'Gisela 5' had a significantly higher fruit diameter than those grafted on 'Santa Lucia 64' rootstock. The fruit diameter of 'Burlat' was much lower compared to 2.01 cm reported by Radicevic et al. (2011) and 2.11 cm measured by Zhivondov (2011). The analyzed cultivars grafted on the 'Gisela 5' rootstock developed averagely significantly heavier stone compared to the 'Santa Lucia 64' rootstock. The average stone weight of the cv. 'Burlat' grafted on the 'Santa Lucia 64' was higher (0.40 g) in relation to the 'Stella' grafted on the same rootstock (0.37 g). The obtained data of 'Burlat' stone weight was slightly higher in relation to the data reported by Zhivondov (2011), Aliman (2008) and Radicevic et al. (2011). The cherry cultivar did not significantly influence the percentage of flesh in the fruit but average fruit ratio was significantly higher in cultivars grafted on the 'Gisela 5' rootstock (93 %) compared to those grafted on 'Santa Lucia 64' (91.1 %). Usenik et al. (2010a) reported that 'Lapins' grafted on 'Gisela 5' rootstock had an average percentage of flesh fruit weight of 91.8 %. Stancevic (1976) and Aliman (2008) reported slightly higher average values of fruit ratio (% of fruit flesh) of 'Stella' (94.91 and 94.88 %). The obtained average fruit ratio of 'Burlat' was also lower compared to the data reported by Aliman (2008) and Radicevic et al. (2011), where the fruit ratio was between 93.73 and 91.85 %. In Table 3 the results of total soluble solids (TSS) and titratable acids content in fruits of cherry cultivars are presented. Table 3: Average content of total soluble solids (° Brix) and titratable acids (%) in fruits of 'Stella' and 'Burlat' cherry cultivars grafted on two rootstocksa Cultivar Rootstock Total soluble solids (°Brix) Titratable acids (% of malic acid) 'Stella' 'Gisela 5' 13.0 a ± 0.29 0.29 a ± 0.10 'Santa Lucia 64' 16.0 b ± 0.20 0.23 b ± 0.08 Average 14.5 a ± 1.70 0.26 a ± 0.04 'Burlat' 'Gisela 5' 13.0 a ± 0.28 0.22 a ± 0.10 'Santa Lucia 64' 12.5 a ± 0.50 0.33 b ± 0.08 Average 12.8 b ± 0.48 0.28 b ± 0.03 Average of 'Gisela 5' 14.3 a ± 0.44 0.26 a ± 0.04 Average of 'Santa Lucia 64' 13.0 b ± 1.95 0.28 b ± 0.08 Cultivar x Rootstock *** NS a Average values ± standard error are presented. Different letters in columns indicate significantly different values at p < 0.05; NS - no significant influence; - indicate significant influence atp <0.001. The average total soluble solids content ranged from 12.5 °Brix in 'Burlat' grafted on the 'Santa Lucia 64' rootstock to 16 °Brix in 'Stella' grafted on the 'Gisela 5' rootstock. Cultivar and rootstock exhibited significant influence on the content of total soluble solids in cherry fruits. The fruits of cv. 'Stella' had significantly higher content of soluble solids in relation to fruits of 'Burlat'. The fruits from the trees grafted on 'Gisela 5' rootstock had significantly higher content of total soluble solids in relation to the fruits from tress grafted on 'Santa Lucia 64'. The results of the average content of soluble solids for the cultivar 'Stella' (14.5 °Brix) are similar to results of Aliman (2008). Albertini and Della Strada (1996) and Stancevic (1976) obtained higher values of this parameter (15.2 and 17.2 °Brix). The obtained results of the total soluble solids in 'Burlat' fruit are lower in relation to Radicevic et al. (2011) and Aliman (2008), which reported that the average content of total soluble solids of 'Burlat' was 13.77 and 15.90 °Brix. Usenik et al. (2010b) reported that leaf/fruit ratio also had significantly influences total soluble solids content in 'Lapins' fruit grafted on 'Gisela 5' rootstock. Cultivar and rootstock had a significant influence on the fruit titratable acids content. Significantly higher average levels of titratable acids were measured in 'Burlat' cultivar than in 'Stella'. The investigated rootstock 'Santa Lucia 64' caused significant increase of titratable acids content of cherry cultivars comapred to the 'Gisela 5' rootstock. In table 4 the results of trunk cross section area (TCSA) and flower index (FI) of 'Stella' and 'Burlat' cherry cultivars grafted on two rootstocks are presented. Table 4: Average values of yield/tree (kg), TCSA (cm2) and flower index (FI) of 'Stella' and 'Burlat' cherry cultivars grafted on two rootstocksa Cultivar Rootstock Yield/tree (kg) TCSA (cm2) Flower index (FI) 'Stella' 'Santa Lucia 64' 21.00 a ± 6.94 47.61 a ± 9.60 0.50 a ± 0.15 'Gisela 5' 22.50 a ± 7.53 54.42 b ± 9.47 0.54 a ± 0.24 Average 21.75 a ± 7.24 51.01 a ± 9.92 0.52 a ± 0.20 'Burlat' 'Santa Lucia 64' 20.00 a ± 6.78 50.64 c ± 10.32 0.26 b ± 0.06 'Gisela 5' 21.50 a ± 7.06 61.64 d ± 10.55 0.60 c ± 0.14 Average 20.75 a ± 6.92 56.14 b ± 11.62 0.42 b ± 0.21 Average of 'Gisela 5' 22.00 a ± 7.30 58.03 a ± 10.44 0.57 a ± 0.20 Average of 'Santa Lucia 64' 20.75 a ± 7.01 49.13 b ± 9.82 0.37 b ± 0.17 Cultivar x Rootstock NS NS *** a Average values ± standard error are presented. Different letters in columns indicate significantly different values at p < 0.05; NS - no significant influence; *** - indicate significant influence atp < 0.001. The average yield of 'Stella' (Table 4) ranged from 21.0 ('Santa Lucia 64' rootstock) to 22.5 kg/tree ('Gisela 5' rootstock). The trees of 'Burlat' averagely yielded from 20.5 to 21.5 kg/tree. There were no significant differences between rootstocks as well as between cultivars in average yield per tree. The results of average yield of 'Gisela 5' rootstock are slightly lower than the results reported by Usenik et al. (2010a). Analyses of variance showed that both factors (cultivar and rootstock) had a statistically significant influence on the TCSA. Trees grafted on 'Gisela 5' rootstock had significant higher average of TCSA (58.03 cm2) compared to trees grafted on the 'Santa Lucia 64' rootstock (49.13 cm2). However, trees grafted on 'Gisela 5' were one year older than trees grafted on the 'Santa Lucia 64' rootstock. Radunic et al. (2011) obtained 40.1 cm2 TCSA for 7 year-old cherry trees trained in a spindle bush training system. The same author reported 40.8 cm2 TCSA for cherry trees trained in the "V" training system. Fajt and Komel (2008) measured an average of 63 cm2 TCSA in 8 year-old cherry cultivars grafted on 'Gisela 5' rootstock. Cultivar and rootstock had a statistically significant influence on the flower index (FI). The average value of 'Stella' flower index was significantly higher compared to the 'Burlat' cultivar. The trees grafted on 'Santa Lucia 64' rootstock had significantly higher average flower index than the trees grafted on 'Gisela 5'. Cultivar 'Stella' grafted on 'Gisela 5' rootstock had a higher average FI compared to 'Burlat' grafted on the same rootstock. 4 CONCLUSIONS Analyses of pomological and phenological characteristics of cherry cultivars 'Burlat' and 'Stella' grafted on the 'Santa Lucia 64' and 'Gisela 5' rootstocks showed that the choice of rootstock had a significant influence on the fruit and tree characteristics. 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Inovacije u vocarstvu, III savjetovanje, Zbornik radova, Poljoprivredni fakultet Beograd: 197-205. 1 COBISS Code 1.01 DOI: 10.2478/v10014-012-0013-4 Agrovoc descriptors: zea mays, maize, cereals, land varieties, energy consumption, energy value, efficiency, productivity, fertilizers, nitrogen fertilizers, plant production, input output analysis Agris category code: f01, e16 Reasearch of Energy use efficiency for maize production systems in Izeh, Iran SH. LORZADEH1, A. MAHDAVIDAMGHANI2, M. R. ENAYATGHOLIZADEH3 and M. YOUSEFI 4 Received March 04, 2012; accepted July 03, 2012. Delo je prispelo 04. marca 2012, sprejeto 03. julij 2012. ABSTRACT IZVLEČEK This study was carried out in Khuzestan province in Iran and aim of investigation was energy analysis (input-output) of maize production systems in Izeh County of Iran. Data were collected from 30 maize farms by using a face to face questionnaire method in 2011. The results revealed that in maize production systems total energy input was 34.640 MJ.ha-1. The highest share of energy consumed was recorded for N fertilizer (20.80%) which is a nonrenewable resource. Output energy was 102.973 MJ.ha-1. Accordingly, energy use efficiency (output-input ratio) was 2.97, energy productivity calculated as 0.20 kg.MJ-1 and net energy was observed as 68.333 MJ.Kg-1. Also, agrochemical energy ratio was 48.97% which is high ratio of input energy in this agro ecosystems. Key words: Energy use efficiency, Maize, Agrochemical Energy productivity, RAZISKAVA ENERGETSKE UČINKOVITOSTI PRIDELAVE KORUZE V IZEHU, IRAN Raziskava energetske učinkovitosti pridelave koruze je bila opravljena v provinci Khuzestan, okrožja Izeh v Iranu. Podatki za raziskavo so bili pridobljeni z ustnim anketiranjem 30 pridelovalcev koruze v letu 2011. Rezultati so pokazali, da je bil celokupen vnos energije v ta pridelovalni sistem 34,640 MJ.ha"1. Največji delež porabljene energije odpade na dušikova gnojila (20,80 %), kar predstavlja neobnovljivi vir. Izplen energije je znašal 102, 973 MJ.ha"1. Učinkovitost izrabe energije (vnos/iznos) je bila 2,97, izračunana energetska produktivnost je bila 0,20 kg.MJ"1, neto energija pridelka je znašala 68,333 MJ.Kg"1. Agrokemijsko energijsko razmerje je bilo 48,97 %, kar predstavlja dokaj velik vnos energije v tem agro"ekosistemu. Ključne besede: izkoristek energije, energetska učinkovitost, koruza, agrokemikalije 1 3 Department of Agronomy and plant Breeding, Shoushtar Branch, Islamic Azad University, Shoushtar, Iran, Lorzadeh42@yahoo.com 2 4 Department of Agroecology, Environmental Sciences Research Institute, Shahid Beheshti Universtity, G.C., Tehran, Iran 1 INTRODUCTION Maize (Zea mays L.) is an important cereal crop of Khuzestan province, Iran. It is grown for fodder as well as for grain purpose in Iran. Approximately 320000 hectares of field corn were grown with a production of 2.560.000 tons an average grain yield of 8000 kg per hectare in Iran in 2010. (Anonymous, 2010). Energy has been a key input of agriculture since the age of subsistence agriculture. It is an established fact worldwide that agricultural production is positively correlated with energy input (TaheriGaravand et al., 2010). Agriculture is both a producer and consumer of energy. Energy input-output analysis is usually used to evaluate the efficiency and environmental impacts of production systems (Ozkan et al., 2004). 2 MATERIALS Izeh(Izeh County (49 31' N, 52 49' E), south of Iran), is one of the important maize production areas in the south part of Iran in Khuzestan province. In this region maize is grown as second crop. For this study data were collected from 30 farms applying a face-to-face questionnaire. Other information was collected from the Ministry of Agriculture. Total energy input and output in maize production systems was estimated by using questionnaires and data analysis. It should be clearly stated that parameters listed in Table 1 were obtained from the questionares and data analysis. Basic information on energy inputs and maize yield were entered into Excel spreadsheets and then energy indicators were calculated according Table 1. Finally energy use efficiency, specific energy, energy productivity and net energy were Energy use in agriculture has been increasing in response to increasing population, limited supply of arable land, and a desire for higher standards of living (Kizilaslan, 2009). In modern agriculture system input energy is very much higher than in traditional agriculture system, but energy use efficiency has been reduced in response to no affective use of input energy. Efficient use of energies helps to achieve increased productivity and contributes to the economy, profitability and competitiveness of agriculture sustainability in rural areas (Ozkan et al., 2004; Singh et al., 2002). The main objective of this study is analysis of energy use and energy indicator of maize production systems in Izeh county of Khuzestan province in Iran. AND METHODS determined applying standard equations (Hatirli et al., 2006; Mohammadi et al., 2010) Energy use efficiency = (output energy (MJ.ha-1)) / (input energy (MJ.ha-1]) (1) Specific energy = (input energy (MJ.ha-1)) / (maize yield (kgha-1)) (2) Energy productivity = (maize yield (kg.ha-1)) / (input energy (MJha-1)) (3) Net energy = output energy (MJ.ha-1) - input energy (MJ.ha-1) (4) Agrochemical energy ratio was calculated by applying Equations 5 (Khan et al., 2009): Agrochemical energy ratio= input energy of agrochemicals (MJha-1) /total input energy (MJ.ha-1) (5) Reasearch of Energy.. .production systems in Izeh, Iran Table 1. Energy equivalents for input and output of Maize production systems in Izeh county Unit Energy equivalents Reference A. Inputs 1. Human labor h 1.96 2. Machinery h 62.7 3. Diesel fuel l 51.33 4. Chemical fertilizer Kg (a) Nitrogen Kg 66.14 (b) Phosphate (P2O5) Kg 12.44 (c)Potassium (K2O) Kg 11.15 5. Chemicals Kg 120 6. Electricity Kwh 3.6 7. Water for irrigation m3 0.63 8. Seed Kg 50.0 B. Output 1. Maize Kg 14.7 [Mohammadi and Omid, 2010] [Samavatean et al., 2010] [Samavatean et al., 2010] [Erdal et al., 2007] [Erdal et al., 2007] [Mohammadi and Omid, 2010] [Demircan et al., 2006] [Rafiee et al., 2010] [Hatirli et al., 2005] [Erdal et al., 2007] [Ozkan et al, 2004; Mandal et al.,2002] The input energy was divided into direct, indirect, renewable and non-renewable energies [Kizilaslan, 2009; Samavatean et al., 2010].Direct energy covered human labour, diesel fuel, water for irrigation, and electricity used in the corn production while indirect energy consists of seeds, pesticide, fertilizers, and machinery energy. Renewable energy consists of human labor and seeds and nonrenewable energy includes diesel, pesticide, fertilizers, electricity and machinery. Also in the last part of the research, economic analysis of corn production was investigated. 3 RESULTS AND DISCUSSION 3.1 Energy use in maize production systems in Izeh County The inputs used and output in maize production systems, their energy equivalents, and percentages in the total energy input presented in Table 2. The results revealed that total energy input in maize production systems was 3464002 MJ.ha-1. N fertilizer used in maize production systems had a high share with 20.80%. Diesel fuel energy used in maize production systems ranked in the second place with 31.60% in the total energy input. The lowest share of total energy was recorded for human lLabour (0.56%) which is a renewable resource of energy. In this study maize grain yield was 7005kg.ha-1 that total energy equivalents for this amount was 102.97MJ.ha- Table 2: Energy inputs, outputs and the ratio of maize production in Izeh county Quantity per unit area (ha) Total Energy equivalents(%) 99.32 17.50 213.51 194.68 1097.25 10959.47 0.56 3.17 31.60 108.68 61.98 37.84 9.25 2000 7327.13 21.63 7188.10 771.03 421.92 1110 7200 4616.10 1081.50 34640.02 20.80 2.23 1.22 3.20 20.80 13.30 3.12 100 Inputs and output - (unit) A. Inputs 1. Human- labour (h) 2. Machinery (h) 3. Diesel fuel (L) 4. Chemical fertilizer (kg) (a) Nitrogen (N) (b) Phosphate (P2O5) (c)Potassium (K2O) 5. Chemicals(kg) 6. Electricity(Kwh) 7. Water for irrigation(m3) 8. Seed (kg) Total input energy B. Output 1. maize grain yield (kg) Total output energy Results of energy indicators for maize production systems are shown in Table 3. Accordingly, energy efficiency (output-input ratio) was 2.97. Lower energy use efficiency in maize production systems is due to higher energy inputs in these systems for example N fertilizer consumed. Such indicator was reported 2.8 for wheat production systems (Streimikiene et al., 2007) and 25.75 for sugar beet (Erdal et al., 2007) in Turkey. 3.2 Energetic of producing maize systems in Izeh County The total means energy input as direct and indirect, renewable, and non-renewable forms for greenhouse and open-field maize production was given in Table 4. The total energy input necessary for maize production was 34640.02 MJ/ha. Out of all 33.74% of the 7005 102973.5 100 102973.5 100 Energy productivity (grain yield per energy input) and specific energy in maize production systems were 0.20 kg.MJ-1 and 9.95 MJ.kg-1 respectively. System net energy (output minus input) was as 68333MJha-1. Agrochemical energy ratio was 48.97% which is a high portion of input energy of maize production systems. It should be mentioned that maize production in south part of Iran could be limited using amounts of chemical fertilizers and pesticides. Quantity 34640 102973 2.97 0.20 68333 total energy, input use in maize production was in the form of indirect energy. The remaining part of energy input use (66.26%) was in the form of direct energy. On the other hand the research results indicate that the total energy input used in maize production systems was mainly dependent on non-renewable energy forms (Table 4). As can be seen from the table, on an average, the non-renewable form of energy input was 83.02% in maize Table 3: Indicators of energy use of Maize production systems in Izeh county Indicators Unit Inputs energy MJ.ha-1 Output energy MJ.ha-1 Energy use efficiency Energy productivity kg.MJ-1 Net energy balance MJ.ha-1 production systems of the total energy input while the 16.98% of input energy was renewable energy resource. The high rate of non-renewable and direct energy inputs indicates an intensive use of chemical fertilizer and diesel fuel consumption in these agroecosystems. Table 4: Total energy input in form of direct, indirect, renewable and non-renewable for maize production in Izeh county Indicators Quantity (MJ ha-1) Percentage (%) Direct energy a 22952.48 66.26 Indirect energy b 11687.54 33.74 Renewable energy c 5881.88 16.98 Non-renewable energy d 28758.14 83.02 Total energy input 34640.02 100 a Includes human labour, diesel, water for irrigation, electricity, b Includes seeds, fertilizers, pesticides, machinery. c Includes human labor, seeds, and water for irrigation. d Includes diesel, pesticides, fertilizers, electricity and machinery. 4 CONCLUSION The important following conclusions are drawn; 1. Total energy input and output in maize production systems were 34640 and 102973 MJ. ha-1. 2. That the highest share of input energy was reported for nitrogen fertilizer, diesel fuel, and water for irrigation (20.80, 31.60 and 13.30%) respectively. 3. The energy use efficiency, energy productivity, specific energy, net energy of maize production systems were 2.97, 0.20 kg MJ-1,10.63MJ.kg-1 and 68333 MJ.ha-1 respectively. 4. The share of total input energy as direct, indirect, renewable and nonrenewable forms were 66.26, 33.74, 16.98 and 83.02% respectively. 5 ACKNOWLEDGEMENT This article is part of a yield investigation in Islamic Azad university of Shoushtar. So we thanks of investigational domain of Shoushtar, specially miss Dialamepoor engineer for every cooperation. 6 REFERENCES Anonymous., 2010. Department of statistics and information, Ministry of Jihad-e-Agriculture, Tehran, Iran. . Demircan V, Ekinci K, Keener HM, Akbolat D, Ekinci C. Energy and economic analysis of sweet cherry production in Turkey: A case study from Isparta province. 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COBISS Code 1.01 DOI: 10.2478/v10014-012-0014-3 Agrovoc descriptors: grapevines, vitis vinifera, genotypes, microsatellites, genetic markers, genetic variation, varieties, land varieties, genetic parameters, designation of origin, quality controls, standardizing, genetic distance, polymorphism, genetic parameters Agris category code: f30, f70 Collection and genetic characterization of Vitis vinifera ' Žilavka' by microsatellites and AFLP markers Lidija TOMIC1, Nataša ŠTAJNER2, Tatjana JOVANOVIC CVETKOVIC1, Miljan CVETKOVIC1 and Branka JAVORNIK2 Received May 23, 2012; accepted September 3, 2012. Delo je prispelo 23. maja 2012, sprejeto 3. septembra 2012. ABSTRACT 'Žilavka' has been grown in Bosnia and Herzegovina since the XlVth century and is exploited for wine production. Although not sufficiently studied, this grapevine cultivar has high economic potential for the country. Five survey missions resulted in the collection of eighty 'Žilavka' accessions that varied in terms of names and characteristics. Because of the unknown origin of the cultivar, these accessions were analyzed with microsatellites markers in order to obtain a standard 'Žilavka' genotype. AFLP markers were used to investigate the genetic basis of variability within the cultivar. 'Žilavka' grapevines were screened on 14 microsatellite loci, thus revealing 4 different genotypes arising from mutations observed at 10 polymorphic loci. AFLP analysis of 52 'Žilavka' accessions revealed 35 different genotypes, with an average polymorphism of 57 %. Cluster analysis showed no grouping of different Žilavka accessions according to their names, characteristics or collection locations. The standard 'Žilavka' genotype was further compared to 211 cultivars from Slovenia (49), Austria/Germany (20), France (13), Portugal (27), Croatia (19), Greece (32), Spain (21) and Italy (30) in order to assess their genetic relationships. In pairwise comparisons, the highest genetic similarity was found with Slovenian cultivars 'Glera' and 'Briška Glera' (64 %) and the highest genetic dissimilarity (100 %) with two Italian cultivars, 'Nebbiolo Lampia' and 'Vespolina'. Inventory, collection and genetic characterization of 'Žilavka' accessions are important steps towards cultivar standardization, identification of parental cultivars and investigation of cultivar origin, required for its sustainable use. Key words: grapevine, microsatellite, standard genotype, variability, AFLP IZVLEČEK ZBIRANJE VINSKE TRTE SORTE ŽILAVKA (Vitis vinifera L.) IN GENETSKA KARAKTERIZACIJA Z MIKROSATELITNIMI IN AFLP MARKERJ 'Žilavka' je pomembna vinska sorta z območja Bosne in Hercegovine kjer jo gojijo že od XIV stoletja. V preteklosti ni bila dovolj proučevana vendar ima velik ekonomski potencial za omenjeno območje. Akcesije žilavke (80), ki imajo različna imena in se razlikujejo po nekaterih osnovnih karakteristikah so bile nabrane na različnih področjih Bosne in Hercegovine. Za pridobitev standardnega genotipa žilavke smo uporabili mikrosatelitne markerje in z analizo 14 lokusov odkrili mutacije na 10 lokusih in določili 4 različne genotipe. Vse akcesije (52) katerim smo na osnovi mikrosatelitov določili standardni genotip smo nadalje analizirali z AFLP markerji in tako določili 35 različnih genotipov. Povprečni polimorfizem pri AFLP analizi je bil 57 %. S klastrsko analizo nismo odkrili skupin povezanih z različnimi karakteristikami, poimenovanjem ali izvorom akcesij žilavke. Standardni genotip žilavke smo nadalje primerjali z genotipi 211 kultivarjev iz Slovenije (49), Avstrije/Nemčije (20), Francije (13), Portugalske (27), Hrvaške (19), Grčije (32), Španije (21) in Italije (30), da bi ugotovili kakšna je sorodnost z njimi. V analizi primerjave parov smo ugotovili, da je žilavka najbolj sorodna (64 %) s slovenskima kultivarjema 'Glera' in 'Briška Glera' ter najbolj genetsko oddaljena od italijanskih kultivarjev 'Nebbiolo Lampia' in 'Vespolina'. Zbiranje, vrednotenje in genetska karakterizacija akcesij žilavke je pomembna za standardizacijo kultivarjev, analizo starševstva in izvora sorte. Ključne besede: vinska trta, mikrosateliti, standardni genotip, variabilnost, AFLP 1 University of Banjaluka, Faculty of Agriculture, Bulevar vojvode Petra Bojovica 1A, 78 000 Banjaluka, Bosnia and Herzegovina, lidija.tomic@agrofabl.org 2 University of Ljubljana, Biotechnical Faculty, Jamnikarjeva 101, SI-1111 Ljubljana, Slovenia 1 INTRODUCTION Vitis vinifera 'Zilavka' is a white grapevine cultivar and is used traditionally for wine production. In the region of Herzegovina (Bosnia and Herzegovina), this cultivar has been grown for more than 600 years, the Bosnian King Tvrtko having been mentioned as drinking Zilavka wine in the 14th century (Vuksanovic and Kovacina 1984). In the 19th century, due to the grape quality and, particularly, to its resistance to bunch rot (Botrytis cinerea Pers.), the Austro-Hungarians exploited this cultivar by the production of a special dessert wine of the Malaga type (Mijatovic 1988). Apart from its historic importance and long tradition, Zilavka wine has high economic potential for Bosnia and Herzegovina, since it is exported and is popular in neighboring countries. It is also grown in adjacent regions of Croatia, Macedonia, Montenegro and Serbia. Vuksanovic and Kovacina (1984), Mijatovic (1988), Tarailo (1991) and Cindric et al. (2000) have provided an ampelographic description of this cultivar, which is characterized by high morphological heterogeneity of various traits: the shape, size and compactness of the cluster, the color, shape and size of the berry, vegetative potential, grape and wine quality, and resistance to bunch rot (Botrytis cinerea Pers.). In 1978 and 1991, clonal selection was performed at various locations and different types of 'Zilavka' were mentioned. Tarailo (1991), who described the clonal selection of 'Zilavka', also reported four different 'Zilavka' types and claimed that they are different genotypes. 'Zilavka' heterogeneity might be a result of ecological/growth factors or genetic mutations. Many authors designate 'Zilavka' as an autochthonous cultivar to Herzegovina (Cindric et al. 2000; Milosavljevic 1998; Buric 1985; Vuksanovic and Kovacina 1984; Licul and Premuzic 1979; Tarailo et al. 1978; Avramov 1974), where it can be found under various synonymic names: 'Zilavka Mostarska' (Cindric et al. 2000; Milosavljevic 1998; Mijatovic 1988), 'Zilavka Hercegovacka' (Cindric et al. 2000; Avramov 1974), 'Zilavka Bijela' (Mijatovic ^ 1988; Avramov 1974), 'Zilavka Zutka' and 'Zilavka Zelenka' (Anicic op cit. Mijatovic 1988). In our study, two different marker systems, microsatellites (SSR - short sequence repeats) and AFLP (amplified fragment length polymorphism), were applied for genetic analysis, thus providing a complementary tool to ampelographic descriptions. Microsatellites are among the most frequently used DNA markers for cultivar identification, revealing synonyms and homonyms and geographical origin, studying genetic relationships within large groups of cultivars and for clonal variability characterization. AFLP has been found to be an efficient and sensitive method for establishing genetic intra-varietal variability. A combination of SSR and AFLP molecular markers is used to obtain a more accurate and complete framework for genomic identity of different accessions within the cultivar (Vignani et al. 2002; Labra et al. 2001). 2 MATERIALS AND METHODS 2.1 Plant material and DNA extraction Survey expeditions were organized to the region of Herzegovina as the traditional centre of 'Zilavka' cultivation. 'Zilavka' was collected from 5 different locations, which were inventoried according to the information received from local people. Four locations belong to the Mostar area (43°20'58''N; 17°48'45''E) and one is from the Trebinje area (42°42'40''N; 18°20'44''E). Three of them are old vineyards established during the seventies, one is a collection vineyard and one is a modern vineyard. Fresh leaves were collected from each of 80 chosen accessions. Plant material of accessions with different characteristics and names ('Starinska Zilavka', 'Zilavka', 'Stara Zilavka', 'Zuta Zilavka', 'Zelena Zilavka') were included in the study (data available upon request). Total genomic DNA was extracted from fresh leaf tissue by CTAB (cetyltrimethylammonium bromide) extraction buffer (Kump and Javornik 1996), re-suspended in TE buffer (1 M Tris-HCl, 0,5 M EDTA, pH 8.0) and stored at 4 °C. 2.2 Microsatellite analysis Eighty 'Zilavka' accessions were analyzed at 14 microsatellite (SSR) loci: VVS2 (Thomas and Scott 1993), VVMD5 and VVMD6 (Bowers et al. 1996), VVMD24 24, VVMD25 25 and VVMD27 27 (Bowers et al. 1999), VrZAG21, VrZAG47, VrZAG62, VrZAG64, VrZAG67 and VrZAG79 (Sefc et al. 1999), and Uch11 and Uch29 (Lefort et al. 2001). The PCR reaction in a total volume of 10 pl contained 20 ng of extracted DNA, 10 x PCR buffer (Fermentas), 0.2 mM dNTP's (Fermentas), 2 mM MgCl2 (Fermentas), 0.5 pM of each primer and 0.5 U of Taq polymerase (Fermentas). One of each of the primer pairs was labeled with fluorescent Cy-5 dye. Amplification of SSR loci was done in a Whatman Biometra T-Gradient thermocycler with the following steps: hot start for 5 minutes at 95 °C; 26-40 cycles of: denaturation at 94 °C for 30-45 seconds, annealing at 50-56 °C for 30-45 seconds and an extension step at 72 °C for 90 seconds. Amplification of loci Uch11 and Uch29 was done by a tailing protocol using three different primers: 0.2 pM of each of unlabelled Uch primers and 0.075 pM of 18 bp M13 tail sequence attached to the forward primer for subsequent fluorescent labeling (5' TGTAAAACGACGGCCAGT '3). An optimized touchdown protocol was used for PCR of these two loci: initial denaturation of 94 °C for 5 minutes: 5 cycles of 94 °C for 45 seconds, 60 °C for 30 seconds with a decrease of -1 °C per cycle and 72 °C for 1.5 minutes; followed by 25 cycles at the annealing temperature of 55 °C. PCR reactions were completed at 72 °C for 8 minutes (incubation). Amplified SSR fragments were denatured for 4 minutes at 95 °C and separated on 6 % polyacrylamide gel electrophoresis containing 7 M urea and detected by an ALFexpress DNA automated sequencer (GE Healthcare). The allele sizes were analyzed with AlleleLocator version 1.03 software (Amersham Pharmacia Biotech, 1998). Alleles were precisely sized against ALFexpress sizer 50 - 500 bp (GE Healthcare) and by internal DNA standards of various sizes amplified from plasmid. 2.3 AFLP Analysis Fifty-two 'Zilavka' accessions were analyzed by 6 different AFLP primer combinations: Msel-CAA/Pstl-ACA, Msel-CAA/Pstl-AAC, Msel-CAT/Pstl-ACA, Msel-AG/Pstl-AGA, Msel-CT/Pstl-ACA and Msel-AG/Pstl-ACA. Isolated DNA (250 ng) was digested by 2.5 U of PstI and 2.5 U of Msel restriction endonucleases (New England Biolabs) in a reaction volume of 40 pl at 37 oC for 3 h. After digestion, 5 pmol of Pst and 50 pmol of Mse double stranded adaptors were ligated (1 Weiss U of T4 DNA ligase) to the sticky ends of the genomic fragments in a final volume of 50 pl at 37 oC for 3 h. Adaptors were obtained by mixing equimolar amounts of primers PstRI linker1 and PstRI linker2 for Pst adapters and Msel linker1 and Msel linker2 for Mse adapters. The pre-amplification procedure was done in a total reaction volume of 50 pl containing: 5 pl of ligation reaction serving as template, 1x PCR buffer, 1.5 mM MgCh, 200 pM each dNTP's, 1.25 U Taq polymerase, 50 ng of both PstI and MseI primers with one selective nucleotide (Pstl+A and Msel+C). Reactions were amplified in a Whatman Biometra T-Gradient thermocycler, repeating 20 cycles of: 94 °C for 30 seconds, 56 °C for 60 seconds and 72 °C for 105 seconds. The PCR products from the pre-amplification step were diluted 10-fold and 5 ^l of the dilution was used for selective amplification. Selective amplification was done by 15 ng of both Pstl and Msel primers with two or three selective nucleotides at the 3' end and Pstl primers were Cy5 labeled at their 5' end to allow automated laser fluorescence analysis. Selective reactions were performed in a 10 ^l PCR reaction mix with the same reaction components as for the pre-amplification step, except that 0.3 U of Taq polymerase was used. The reaction was amplified with an initial touch down protocol: 94 °C for 30 seconds, 65 °C for 30 seconds and 72 °C for 60 seconds with a touchdown of - 0.7 °C of annealing temperature per cycle, followed by 23 cycles at 94 oC 30 s, 56 oC 30 s and 72 oC 1 minutes, and the samples were immediately transferred onto ice. The amplification reaction was mixed with an equal volume (10 ^l) of formamide loading buffer (5 mg dextrane blue in 1 ml of formamide), denaturated by heating to 94 oC for 4 minutes. Five ^l of sample was loaded onto 5% polyacrilamide denaturating gel (5% acrylamide-bisacrylamide 19:1, 1*TBE, 7 M urea) and electrophoresed on an ALFexpress DNA automated sequencer (GE Healthcare). An external size standard ranging from 50 to 500 bp was run together with samples to allow further sizing of the fragments. AFLP bands ranging from 50 to 500 base pairs were analyzed using AlleleLocator version 1.03 software, (Amersham Pharmacia Biotech, 1998). In the first instance, all 80 accessions were included in AFLP testing but only 52 produced scorable fingerprints and were included in the AFLP analysis. 2.4 Data analysis Microsatellite and AFLP amplified bands across all analyzed loci were scored by state as present and given numerical value 1 or absent 0, making a presence-absence matrix of bands. This matrix served as a basis for clustering and assessing overall similarity among the analyzed accessions. A similarity index was calculated from band sharing data of each pair of accessions using the Jaccard (1908) coefficient of similarity. A dendrogram was constructed from the matrix of pairwise distances using an unweighted pair group method (UPGMA) for clustering in the NTSYS-PC software package, version 1.80. The obtained microsatellite profile of 'Žilavka' was further compared to 211 already genotyped cultivars in Europe in order to assess their genetic relationships. For AFLP analysis, the percentage of polymorphism was calculated for each primer pair combination from the total number of amplified bands and the number of polymorphic bands. 3 RESULTS AND DISCUSSION 3.1 Microsatellite analysis Eighty 'Zilavka' accessions were screened on 14 microsatellite loci. These analyses resulted in 4 different genotypes arising from mutations observed at 10 polymorphic loci (Tab. 1). Seventy-seven accessions had the same allelic profile across all 14 loci and could be considered as a standard genotype for 'Zilavka'. Three accessions (9/2, 10/2 and 11/2), which were thought to be 'Zilavka', resulted in polymorphism at 5 to 6 loci (Tab. 1) and could not be considered to be 'Zilavka'. Table 1: Standard 'Zilavka' genotype profiled at 14 microsatellite loci with three distinguished genotypes and 'Chardonnay' as reference cultivar. Genotype 'Zilavka' 9/2 10/2 11/2 'Chardonnay' VVS2 132:152 n.a. 132:152 132:152 137:152 VVMD5 226:238 226:238 226:238 226:238 232:236 VVMD6 208:208 208:208 190a:208 208:208 198:208 VVMD24 208:208 208:208 208:208 208:208 208:216 VVMD25 240:242 250a:250a n.a. 240:242 240:256 VVMD27 179:194 179:194 181a:194 179:194 n.a. VrZAG21 201:203 201:206b n.a. 201:206b 200:206 VrZAG47 158:173 158:173 158:173 158:173 160:168 VrZAG62 189:189 189:189 189:189 189:205a 188:196 VrZAG64 144:144 160b:164b 144:144 160b:164b 160:164 VrZAG67 151:161 141b: 151 141b:141b 141b: 151 140:153 VrZAG79 249:249 237b:249 242a:258a 237b:249 244:246 Uch11 235:235 235:235 235:235 235:249a 248:263 Uch29 208:295 208:295 295:306a 208:295 289:297 "new alleles different from standard 'Zilavka' genotype, balleles shared between distinguished 'Zilavka' genotypes, n.a. no amplification However, detailed morphological description of these accessions should be performed for clear definition. Grapevine cultivars are vegetatively propagated and individuals of one cultivar are expected to be genetically identical to each other, but some cultivars may comprise several different genotypes due to a polyclonal origin (Kozjak et al. 2003) or somatic mutations can be accumulated over years of clonal propagation. Comparison of standard 'Zilavka' from our analyses with 'Zilavka' from Croatia, genotyped by Maletic et al. (1999) resulted in the same allelic profiles at all 7 comparable loci, which confirmed the trueness to type of the 'Zilavka' genotype. The standard 'Zilavka' genotype was further compared to 211 cultivars, from Slovenia (49), Austria/Germany (20), France (13), Portugal (27), Croatia (19), Greece (32), Spain (21) and Italy (30) in order to assess their genetic relationships. Comparison was enabled by using one reference cultivar, 'Chardonnay', for allele size standardization. The proportion of shared alleles was used as the basis for distance measurement among analyzed varieties. In pairwise comparisons of 'Žilavka' with cultivars from the various European regions, the highest genetic similarity was found with a Slovenian cultivar 'Glera' (64 %) and the highest genetic dissimilarity (100 %) with two Italian cultivars, 'Nebbiolo Lampia' and 'Vespolina'. A phenogram of all 211 genotypes was constructed (data available on request) in order to illustrate the genetic relationships between 'Žilavka' and other European cultivars. 'Žilavka' clustered together with Slovenian old cultivars 'Glera', 'Briška Glera', 'Vitovska', 'Zunek', 'Duranja' and 'Popetre'. 3.2 AFLP analysis Fifty-two accessions of standard 'Žilavka' genotype analyzed at 14 microsatellite loci were included in further AFLP analysis. Six primer pair combinations generated 163 scorable bands, of which 87 (57%) were polymorphic, expressing intra-varietal variability (Tab. 2). Table 2: Characteristics of analyzed AFLP loci expressed by number of amplified bands, polymorphic bands and % of polymorphism. Primer pair combination Number of amplified bands Number of polymorphic bands Polymorphism (%) MseI-CAA / PstI-ACA 15 13 87 MseI-CAA / PstI-AAC 20 18 90 MseI-CAT / PstI-ACA 13 5 38 MseI-AG / PstI-AGA 44 27 61 MseI-CT / PstI-ACA 36 11 31 MseI-AG / PstI-ACA 35 13 37 Total 163 87 57 (Average) The degree of polymorphism was higher than reported previously for some cultivars, e.g., 'Carmenere' (2.3%) (Moncada and Hinrichsen 2007), 'Cabernet Sauvignon' (5.9%) (Moncada et al, 2005) or 'Traminer' (34%) (Imazio et al. 2002). The high level of detected polymorphism might be explained by the accumulation of somatic mutations over years of cultivation. 'Zilavka' was spontaneously propagated for many years without formal selection of clones, which might also have resulted in higher heterogeneity within the cultivar. Based on AFLP data, the 52 'Zilavka' accessions revealed 35 genotypes, which are clustered on the dendrogram (Fig. 1). Main AFLP cluster 0.70 0.75 080 0.85 0.90 095 1.00 Genetic Similarity Figure 1: Dendrogram showing genetic similarity among 'Žilavka' accessions generated from AFLP data The clustering of accessions did not correlate locations. The main AFLP cluster consists of with their names, characteristics or sampling 16 non-differentiated accessions of the standard 'Zilavka' genotype, which had previously been differentiated by their different names, characteristics or sampling locations (data available upon request), which means that AFLP analysis revealed no type specific marker. Three out of 52 accessions had an AFLP genetic similarity lower than 0.90 (33/5, 6/5 and 2/1). On the basis of some reports (e.g., Cervera et al. 2000, 1998), accessions showing similarities > 0.90 can be considered to belong to the same cultivar, while the cultivars that are different show similarities between 0.65 -0.90). These three accessions all belong to the standard 'Zilavka' genotype according to the SSR analysis, but further detailed morphological analyses should be done before reaching any final conclusions. 4 DISCUSSION Identification and distinction of 'Zilavka' accessions was possible on the basis of two marker systems. Microsatellite markers enabled determination of a standard 'Zilavka' genotype and, together with AFLP markers, revealed intra-varietal polymorphism. The two molecular markers, SSR and AFLP, explore different parts of the genome and have a different structure in terms of primer sequences and amplified motifs, so they are both valuable for obtaining reliable results on accession variability. Molecular analysis has shown that 'Zilavka' is not a highly homogenous cultivar (high polymorphism is observed), which can be explained by non-formal clonal selection of Zilavka in Bosnia and Herzegovina and also by the long cultivation period, resulting in an accumulation of mutations. Microsatellite genotyping enabled us to exclude the accessions that are different from the true-to-type 'Zilavka', since it is known that different cultivars show at least four allelic differences, while clones show fewer differences but can also be distinguished in some cases by SSR analysis (Laucou et al. 2011). In our study, 80 different accessions of 'Zilavka' were sampled from 5 locations (data available on request) but molecular analysis revealed no clustering of 'Zilavka' accessions according to the observed characteristics, names or locations. Detailed research on ampelographic data needs to be performed to explain the high AFLP polymorphism obtained for three accessions (33/5, 6/5 and 2/1) and to confirm their different origin. The remaining accessions analysed with AFLP markers expressed lower AFLP polymorphism (< 0.90) explaining their intra-varietal variability and true-to-type identity, which was also confirmed by SSR genotyping. 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COBISS Code 1.01 DOI: 10.2478/v10014-012-0015-2 Agrovoc descriptors: solanum tuberosum, potatoes, root vegetables, sprayers, nozzles, application methods, chemical control, control methods, fungicides, plant protection, disease control, equipment, plant protection equipment, equipment, equipment parts Agris category code: h20, n20 Improved quality of fungicide deposition and coverage of potato leaves using flat fan air-injector nozzle IDK Filip VUCAJNK1, Rajko BERNIK2 Received January 16, 2012; accepted February 20, 2012. Delo je prispelo 16. januarja 2012, sprejeto 20. februarja 2012. ABSTRACT IZVLEČEK The aim of our experiment was to improve fungicide spray deposition and coverage of potato leaves by using air-injector nozzle types. We used two standard nozzle types - a flat fan nozzle ST and a hollow cone nozzle TR, as well as a couple of air-injector nozzle types - an air-injector compact nozzle IDK and a symmetric double flat fan air-injector nozzle TWIN (with a 30 ° forward and a 30 ° backward spray jet angle). Water-sensitive paper was placed on the upper, middle and lower part of the plant in order to determine the quality of fungicide deposition and the ability of droplets to penetrate lower parts of the plant. When using the air-injector compact nozzle IDK, potato leaves were covered well at all three levels of the plant. The use of the above-mentioned nozzle resulted in the lowest reduction in coverage value and droplet impression area from the top towards the lowest part of the plant. Furthermore, the nozzle created large enough droplets with sufficient mass and speed to penetrate the dense canopy all the way to the lowest part of the plant. When using the symmetric double flat fan air-injector nozzle TWIN, the angle of both spray jets was excessively wide in order for the droplets to reach the lower part of the plant despite a very large droplet impression area. The use of both standard nozzle types resulted in a poor spray mixture coverage of the middle and lower part of the plant. This predominantly occurred due to insufficient droplet size and the subsequent lack of kinetic energy. Results show that the use of a newer air-injector compact nozzle IDK improves the deposition and coverage of potato leaves with spray mixture. Key words: deposition, coverage, nozzles, potato, fungicide IZBOLJŠANJE DEPOZICIJE IN POKRITOSTI LISTOV KROMPIRJA S ŠKROPILNO BROZGO PRI UPORABI INJEKTORSKE ŠPRANJASTE ŠOBE IDK Namen poskusa je bil izboljšanje nanosa in pokritosti listov krompirja s škropilno brozgo pri uporabi novejših izvedb injektorskih šob. Uporabili smo dve standardni izvedbi šob, špranjasto šobo ST in vrtinčno šobo TR ter dve injektorski izvedbi šob, šobo IDK in šobo z dvojnim simetričnim curkom TWIN (škropilni curek pod kotom 30 o naprej in 30 o nazaj). Na zgornji, srednji in spodnji del rastline smo namestili na vodo občutljive lističe, da bi pri uporabljenih šobah ugotovili kakovost fungicidnega nanosa in sposobnost prodiranja kapljic v spodnje dele rastlin. Ugotovili smo, da je bila najboljša pokritost listov krompirja na vseh etažah pri uporabi injektorske šobe IDK. Pri tej šobi je bilo najmanjše zmanjšanje odstotka pokritosti in površine odtisa posamezne kapljice od vrha proti spodnjemu delu rastline. Ta šoba tvori dovolj velike kapljice, ki imajo veliko hitrost in zadostno maso, da lahko prodrejo skozi gost listni sestoj do spodnjega dela rastline. Pri injektorski šobi z dvojnim simetričnim curkom TWIN je bil kot obeh škropilnih curkov prevelik, da bi kapljice zadele spodnji del rastline, kljub temu da je bila površina odtisa posamezne kapljice zelo velika. Pri obeh standardnih izvedbah šob je bila preslaba pokritost s škropilno brozgo v srednjem in spodnjem delu rastline predvsem zaradi premajhnih kapljic in posledično premajhne kinetične energije. Rezultati kažejo izboljšanje depozicije in pokritosti listov krompirja s škropilno brozgo pri uporabi novejše injektorske šobe IDK. Ključne besede: nanos, pokritost, šobe, krompir, fungicid 1 Ph.D., University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, SI-1111 Ljubljana, e-mail: filip.vucajnk@bf.uni-lj.si 2 Prof., Ph.D., Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, SI-1111 Ljubljana 1 INTRODUCTION Spray deposition on the target surface proved to be the decisive factor in spraying with plant protection products (PPP). It is possible to affect the quality of spray deposition on the target surface by changing droplet size, volume application rate, pressure and driving speed. Fine droplets can provide better fungicide coverage, however, with a less-effective droplet penetration through the canopy (Stangl, 2009). Required volume application rate and adequate fungicide deposition rate result in a good spray coating on the target surface and represent the basic requirement for an effective disease control. Lower volume application rate results in a smaller number of droplets and a smaller spray coating on the target surface (Brune, 2011). Potato has a different morphology than other cultivated plants. Its leaf-area index (LAI) is 4 and it has a complex system of intertwined stems and leaves at different levels which proves to be problematic for the penetration of fungicides through the canopy. Spray deposit should equally cover all parts of the plant in the highest possible degree. Potato has villous leaves and stems with cuticles enabling a quality fungicide deposition. Potato epidermis, on the other hand, does not have an extra epicuticular wax layer, characteristic of some other plants, such as oilseed rape, cabbage etc. (Strasburger, 1991). When spray droplets touch the leaf surface, they stick to it and finally rearrange throughout the surface. There is no risk of droplets bouncing off the leaves or trickling away (Luckhard and Brune, 2011). In the potato late blight control, timely spraying and high-quality fungicide deposition are of extreme importance. The chemical control should involve nozzles with medium droplet size (VMD 250-350 |m). Nozzles with a spray jet at a certain angle from the vertical allow a better leaf coverage, particularly during the main stem elongation and all the way to the point where plants meet between the rows (BBCH 301-309) (Spray Application Technique, 2003). Nowadays, new spraying techniques are being introduced and tested in the potato late blight control. These involve reduced volume application rate (less than 50 l/ha) in Danfoil sprayers, use of standard nozzles on airassisted sprayers, under leaf fungicide deposition and use of nozzles with different spray jets on classic sprayers (Kryger Jensen, 2007). Several authors determined the effect of various nozzle types on the coverage of potato leaves with fungicides. According to Kierzek and Wachowiak (2009), the best coverage of potato leaves can be achieved by using drift-reducing nozzles and double flat fan nozzles. On the lower part of the plant, coverage of the upper part of the leaves was 3 to 5 times better than on the lower part of the leaves. Furthermore, Kierzek and Wachowiak (2007) determined the highest spray deposit and the best coverage of potato plant with the use of a special flat fan nozzle with a spray jet revolved backwards at a 30 ° angle from the vertical. An air-assisted sprayer was used in the trial. Air-injector flat fan nozzle with a single spray jet and standard flat fan nozzle were both less effective in the coverage of potato leaves. Kryger Jensen (2007) stated a similar biological efficacy of air-injector nozzles in comparison with standard and drift-reducing nozzles. Backward angled nozzles proved to reach a better coverage of potato leaves than nozzles with a vertical spray jet. At times, airassisted sprayers prove to be more biologically effective. With Danfoil sprayers, smaller volume application and fungicide deposition rates may be used. This could, however, result in reduced biological efficacy. Under-leaf deposition of spray mixture may improve the efficacy but it would simultaneously reduce the area efficiency and raise the expenses (Kryger Jensen, 2007). According to Klausen (2007), air-injector nozzles proved to be more effective in the coverage of potato leaves in comparison with standard nozzles. The coverage on the upper part of the plant was better when air-assisted sprayers and Danfoil sprayers had been used. The use of Danfoil sprayers resulted in the best coverage of the middle part of the plant. With a reduced volume application rate (120 l/ha), the largest coverage was reached by airassisted sprayers and Danfoil sprayers. Kierzek (2007) compared the fungicide deposition quality on potato plants between a standard nozzle with a vertical spray jet and a nozzle with a 45 ° spray jet. In comparison with the standard nozzle, the latter reached an approximately 50% better coverage of the upper part of the leaves. Coverage of the lower part of the leaves with the nozzle having a 45 ° spray jet was 3-5 times better. Gajtkowski et al. (2005) determined that, in comparison with air-injector nozzles, the use of standard nozzles results in a better coverage of potato leaves. With the pressure raised from 2 to 4 bars, the number of droplets per cm2 when air-injector nozzles had been used was reduced under the allowed limit (20 droplet impressions per cm2). Stallinga et al. (2010) wanted to determine the effect of driving speed and various nozzle types on spray deposition quality and biological efficacy of Shirlan fungicide (AI fluazinam) in potato late blight control. At the referential 100% application rate, there were no statistically significant differences. They did, however, occur with smaller fungicide and volume application rates (65 and 135 l/ha respectively). Standard nozzles reached better results than air-injector nozzles. An increase of the driving speed from 2 to 4 m/s reduced biological efficacy of the fungicide used at the referential 100% application rate. Furthermore, droplet impression number per cm2 dropped by 40-75%. Authors discovered that the droplet impression number per cm2 lower than 120 reduces biological efficacy. Coverage value and droplet impression number per cm2 were reduced, from the top towards the lower part of the plant. Knewitz and Koch (2010) established that, in comparison with single spray jet air-injector nozzles, the use of symmetric double flat fan air-injector nozzles resulted in a better coverage of potato plant. The coverage reached by using the asymmetric double flat fan air-injector nozzle was, however, slightly smaller than with other air-injector nozzle types. Luckhard and Brune (2011) confirmed a much better spray deposition on the upper two thirds of the plant in comparison with the lower third of the plant, regardless of the nozzle type. In comparison with other air-injector nozzle types, the use of symmetric double compact air-injector nozzles resulted in a better coverage of potato plant. Asymmetric and symmetric double flat fan air-injector nozzles reached better coverage values than single spray jet air-injector nozzles. Due to a smaller number of droplets, the coverage of potato plant at a 150 l/ha volume application rate was much smaller than at 350 l/ha. Due to a smaller number of coarse droplets, droplet impression mass on the upper third of the plant was relatively high, whereas the coverage value was small. Despite the extremely coarse (450-575 |m) and coarse (350-450 |m) volume median diameter (VMD) of droplets formed by nozzles, spray deposition on the leaves was good due to a special leaf surface structure of potato plant. Fungicide deposition quality proved to be better at a 350 l/ha than at a 150 l/h volume application rate. The aim of the trial was to determine the spray deposition quality on potato leaves according to various nozzle types. Furthermore, we wanted to research the coverage of potato leaves with spray mixture on the lower part of the plant and to determine which nozzle type is the most suitable one for penetrating the thick canopy, from the top towards the lower part of the plant. Two standard nozzle types were used in the trial, namely a flat fan nozzle ST and a hollow cone nozzle TR. We also included two newer nozzle types - a single spray jet air-injector compact nozzle IDK and a symmetric double flat fan air-injector nozzle AVI-TWIN. In Slovenia, it is customary to use standard nozzles. Air-injector nozzles, on the other hand, are used less frequently. We were interested in finding out whether the new nozzle types ensure a better spray deposition on potato leaves in comparison with standard nozzles. We put forth a hypothesis that, particularly in the middle and lower part of the plant, the use of the two air-injector nozzle types ensures a better spray deposition in comparison with the two standard nozzle types. Moreover, we presumed that both air-injector nozzle types are able to penetrate the canopy better than the standard nozzle types. 2 MATERIALS AND METHODS 4 different nozzle types - 2 standard ones and 2 air-injector ones - were used in the potato spraying trial (Figure 1). Among the standard nozzle types, there were a standard flat fan nozzle ST 110-03 and a standard hollow cone nozzle TR 80-03 C, while air-injector nozzle types included a flat fan air-injector nozzle IDK 120-03 C and a symmetric double flat fan air-injector nozzle AVI TWIN 110 03. The latter had a 30 ° forward and a 30 ° backward spray jet in accordance with the spraying direction. ST TR IDK TWIN Figure 1: Nozzles used in the trial The trial was performed on lighter soil, in Dol pri Ljubljani, in the year 2009. The trial was based on 3 random blocks with 3 repetitions within trial units. Each of three block was 12 m wide and 5 m long. 10 m divider strips were created among the blocks. Within each block, various nozzle types were randomly distributed along the spray boom. Nozzles of the same type were placed together in groups of 4 or 5, it means 2 to 2.5 m wide. In the trial, a medium-to-late Aladin potato cultivar was used at a 75 cm inter row width. Potatoes were planted at a distance of 29.6 cm, creating an exact tuber density of 45,000/ha. During the inflorescence emergence, when approximately 40% of flowers were already open (BBCH 604), potato was sprayed with systemic and contact fungicide Melody Duo (AI iprovalicarb and propineb) at a 2.5 kg/ha application rate. This fungicide is used in potato late blight (Phytophthora infestans) and early blight (Alternaria solani) control during the period of intensive growth. During the spraying, plants were 70 cm high. Each treatment involved three randomly selected plants in the same row. The chosen plants were always located in the middle, on the spot corresponding to the third nozzle (out of five) of each nozzle type. We thus managed to avoid the edge effect of spray jets from the adjacent nozzle types on our measuring place. We attached water-sensitive paper to the upper leaf surface in the upper (70 cm from the ground), middle (40 cm from the ground) and lower part (10 cm from the ground) of the plant (Figure 2). This was done with the aid of paperclips. There was approx. 30 cm of vertical distance among various measuring papers. Measuring papers were 76 mm long and 26 mm wide. Each treatment involved 9 measuring papers. Due to a possible effect of tractor/sprayer passage on the spray deposition on measuring papers, measurements were not performed along the tramlines. Tractor mounted sprayer with a 600 l tank capacity and a 12 m wide spray boom was used in the trial (Figure 3). Spray boom was located 50 cm from the target surface. Driving speed during the spraying was 4.1 km/h and working pressure amounted to 4.0 bars. There was a 400 l/ha volume application rate. Volume median diameter (VMD) of droplets for each nozzle type is shown in Table 1. Air temperature during the spraying was 15 °C, with a 67% relative air humidity and a 0.8 m/s wind speed. After the spraying, measuring papers were collected and analysed. Figure 3: Spraying the field trial with tractor mounted sprayer Table 1: VMD of droplets and droplet distribution according to BCPC and ASAE for each nozzle used in the trial, the pressure of 4.0 bars was used in all cases Nozzle type VMD (^m) Droplet distribution according to BCPC and ASAE ST 110-03 200 fine IDK 120-03 C 380 coarse AVI-TWIN 110-03 410 coarse TR 80-03 C 100 very fine Droplet impressions on measuring papers were analysed with Optomax Image Analyser. Three measurements were performed on each measuring paper. In the APA 2001 V5.1 program, we calculated the coverage value and the droplet impression number per cm2. Based on this data, impression area of a single droplet was calculated as a quotient of coverage value and droplet impression number per cm2. In addition, relative reductions in coverage value and impression area of a single droplet, from the top towards the lowest part of the plant, were analysed. Coverage value and impression area of a single droplet on the upper part of the plant meant 100%. Statistical analysis was performed according to the procedure valid for random blocks with repetitions within the trial units (Kosmelj, 2001; Hadzivukovic, 1991). We initially examined homogeneity of variance, using Hartleys test. Coverage value data, relative reduction in coverage value and relative reduction in impression area of a single droplet were then transformed with the asin (sqrt) function. Analysis of variance and Duncan's Multiple Range Test were performed at a = 0.05. A separate analysis of the upper, middle and lower part of the plant was performed. It was followed by a joint analysis of separate parts of the plant. This gave us a more accurate picture on the spray deposition on the target surface according to individual nozzle types. If present, statistically significant differences among various treatments were marked with different letters. All statistical analyses were performed by the Statgraph 4.0 program (Statistical Graphics Corp., Manugistics, Inc.). 3 RESULTS AND DISCUSSION In comparison with the symmetric double flat fan air-injector nozzle TWIN (37%), the standard hollow cone nozzle TR reached better coverage value (47%) on the upper part of the plant (Figure 4). It is presumed that the slightly higher coverage value of the standard hollow cone nozzle TR was the result of a higher droplet impression number per cm2 (65) when compared with both air-injector nozzle types, namely IDK and TWIN (with 40 and 42 droplet impressions respectively). Compared to the TR nozzle, the IDK nozzle forms a smaller number of droplets, which are, however, coarser, causing the lack of statistically significant differences in the coverage value. TR nozzle forms a larger number of very fine droplets with the volume median diameter of 100 pm. Results of the impression area of a single droplet amounting to 0.72 mm2 partially prove that fact (Figure 6). Volume median diameter of the symmetric double flat fan air-injector nozzle TWIN was probably excessive (approx. 410 pm), causing the coverage value of this nozzle to be slightly lower. Higher pressure values and a slightly higher number of droplets per cm2 would raise the coverage value resulting from the use of this nozzle. According to nozzle producer Agrotop (2010), TWIN nozzles allow a better spray deposition on the vertically positioned plant parts in comparison with the horizontal parts, i.e. leaves on the upper part of the plant, which might be the cause of a slightly worse coverage value. Gajtkowski et al. (2005) stated that good fungicide deposition onto potato plants should involve at least 50 droplet impressions per cm2 and a coverage value higher than 15%. In our trial, both air-injector nozzle types proved to deposit less than 50 droplets per cm2. On the other hand, the coverage value they reached largely exceeded the above-mentioned 15%. Due to this fact, the quality of spray deposition was very high with air-injector nozzles as well. Results of coverage value indicate a very good quality of fungicide deposition on the upper part of the plant with all nozzle types used in the trial. This was concluded due to the fact that the upper part of the plant does not impede the droplets to reach the target surface. Moreover, its leaves are well exposed to the spray deposition. Our results partially correspond to the results of Gajtkowski et al. (2005), who stated that, in comparison with air-injector nozzles, the use of standard nozzles results in a better coverage of potato leaves. In our trial, this held true merely for the standard hollow cone nozzle TR in the upper part of the plant. In the middle part of the plant, the single spray jet air-injector compact nozzle IDK reached a significantly higher coverage value (31%) than standard ST and TR nozzles (with 22 and 20% respectively). (Figure 4). Due to a larger volume median diameter, IDK nozzles seem to be more efficient in the penetration through the canopy, whereas the droplets formed by standard ST and TR nozzles are too small and do not have enough speed and kinetic energy to penetrate deeper into the lower parts of the plant. These results partially correspond to Klausen's findings (2007). The latter proved that the use of air-injector nozzles results in a better coverage of potato plant in comparison with the use of standard nozzles. In our trial, this held true for the middle part of the plant, and not the upper one. As anticipated, in the middle part of the plant, both ST and TR standard nozzle types proved to have a higher droplet impression number per cm2 than the IDK and TWIN air-injector nozzles (Figure 5). Nevertheless, the droplets formed by both ST and TR standard nozzles were much smaller than those of the IDK and TWIN air-injector nozzles. This was, furthermore, proved by the results of the impression area of a single droplet. With both IDK and TWIN air-injector nozzles, the impression area of a single droplet proved to be bigger (0.45 and 0.60 mm2 respectively) than with the ST and TR standard nozzles (0.21 and 0.18 mm2 respectively) (Figure 6). When comparing the two air-injector nozzles, the single spray jet IDK nozzle proved to reach a higher droplet impression number per cm2 (68) than the symmetric double flat fan nozzle TWIN (42). It is thus possible to conclude that both spray jets of the TWIN nozzle have an excessive forward and backward angle which disabled them from sending the droplets deeper into the canopy. In comparison with the upper part of the plant, the middle part had a lower coverage value regardless of the nozzle type. This was anticipated as leaves present a physical obstacle in droplet penetration to the lower-lying parts of the plant. The velocity of fine standard nozzle droplets is lower, causing them to stop earlier on their way in comparison with coarser air-injector nozzle droplets. The latter have a bigger mass, a greater velocity and, therefore, a larger kinetic energy. This is why they are able to penetrate the lower-lying parts of the plant. The increase of the vertical distance between the nozzle and the target surface resulted in a higher droplet impression number per cm2. It can be assumed this occurred due to a bigger overlap of spray patterns from the adjacent nozzles and finer droplets. In comparison with the upper and middle part, the lower part of the plant reached the lowest coverage value with all nozzle types (Figure 4). In this aspect, the results correspond to the Luckhard and Brune's results (2011). The authors determined that, on the upper two thirds of the plant, the quality of spray deposition is much higher than on the lower third of the plant regardless of the nozzle type used. Similar to the middle part of the plant, the use of the single spray jet air-injector compact nozzle IDK resulted in a better coverage value (23%) of the lower part of the plant in comparison with other nozzle types (16-18%). Reasons for a quality spray deposition on the lower part of the plant by the IDK nozzle are identical to those for the middle part of the plant. The nozzle has a single vertical spray jet of coarse droplets at a high velocity, which are able to penetrate all the way to the lowest parts of the plant. The ST, TR and TWIN nozzles all reached coverage values which were only slightly higher than 15%. According to Gajtkowski et al. (2005), that is the lower limit for a quality fungicide application onto potato plants. Moreover, with the majority of nozzle types, the droplet impression number per cm2 was higher on the lower part of the plant than on the middle part of the plant (Figure 5). As already mentioned, this is connected with the increase of distance between the target surface and the nozzle which causes an even bigger overlap of spray patterns from the adjacent nozzles and the reduction in droplet size. With all nozzle types, impression area of a single droplet was smaller on the leaves of the lower part of the plant than in its middle (Figure 6). However, the impression area of a single droplet reached with both IDK and TWIN air-injector nozzle types (0.27 and 0.28 mm2 respectively) was statistically higher than with both ST and TR standard nozzles (0.16 and 0.13 mm2 respectively). Figure 4: Coverage value on the upper, middle and lower part of the plant and on the whole plant according to the nozzle type; UP - upper part of the plant; MP - middle part of the plant; LP - lower part of the plant; W -the whole plant; * means, at the same part of the plant, followed by different letters are significantly different (p < 0.05); bars represent standard errors. ft ft ft ft ft a i-in Figure 5: Droplet impression number on the upper, middle and lower part of the plant and on the whole plant according to the nozzle type; UP - upper part of the plant; MP - middle part of the plant; LP - lower part of the plant; W - the whole plant; * means, at the same part of the plant, followed by different letters are significantly different (p < 0.05); bars represent standard errors. 50 ab 40 b b 30 a a a b 47 a 43 a 42 20 a 37 a a 32 31 28 27 26 26 23 22 10 20 18 6 16 0 UP W c c c b 80 - b b 60 109 a 88 86 a 40 68 65 65 62 55 47 42 42 20 - 40 0 UP MP W ft ft -h 0,28 lh ST IDK TR ST IDK TR ST IDK Figure 6: Impression area of a single droplet on the upper, middle and lower part of the plant and on the whole plant according to the nozzle type; UP - upper part of the plant; MP - middle part of the plant; LP - lower part of the plant; W - the whole plant; * means, at the same part of the plant, followed by different letters are significantly different (p < 0.05); bars represent standard errors. idk twin |tr up idk twin |tr MP idk twin |tr LP 1,4 1,2 - b 1,0 a 0,8 - b 0,6 b 0,87 0,4 - 0,72 0,68 b 0,60 a 0,56 0,50 a 0,45 a 0,2 a 0,30 0,27 0,18 0,0 TR ST UP W & 80 - b b 60 b a a a a 40 - 72 70 54 52 42 42 20 38 38 0 ST Figure 7: Relative reduction in coverage value on the middle and lower part of the plant in comparison with the upper part of the plant according to the nozzle type; UP - upper part of the plant; MP - middle part of the plant; LP - lower part of the plant; W - the whole plant; * means, at the same part of the plant, followed by different letters are significantly different (p < 0.05); bars represent standard errors. Figure 8: Relative reduction in impression area of a single droplet on the middle and lower part of the plant in comparison with the upper part of the plant according to the nozzle type; UP - upper part of the plant; MP - middle part of the plant; LP - lower part of the plant; W - the whole plant; * means, at the same part of the plant, followed by different letters are significantly different (p < 0.05); bars represent standard errors. In comparison with the upper part of the plant (100%), the use of IDK and TWIN air-injector nozzle types reduced the coverage value on the middle part to 72 and 70% respectively (Figure 7). A much bigger reduction occurred with the two standard nozzle types. The ST nozzle reduced the coverage value to 52%, while the reduction of the TR nozzle amounted to 42%. The reduction in coverage value on the lower part of the plant was even more distinctive than on the upper part. Once again, the use of standard ST and TR nozzles resulted in a higher reduction (38% of value in comparison with the upper part) than the two air-injector nozzle types - IDK and TWIN (with a 54 and 42% reduction in comparison with the upper part). The above-cited results show that, predominantly with the air-injector nozzle IDK, the coverage value drops throughout the whole plant height downwards by slightly less than 50%. Based on this it is possible to conclude that, when this nozzle is used, a sufficient number of droplets penetrate all the way to the lower part of the plant in order to cover a sufficiently large area. With other nozzle types, particularly the standard ST and TR nozzles, the coverage value is reduced by slightly less than 66%. When comparing the relative reduction in impression area of a single droplet, from the upper towards the lower part of the plant, the relative reduction was the lowest both in the middle part (reduced to 69% of the upper part value) and the lower part of the plant by the TWIN nozzle (reduced to 32% of the upper part value) (Figure 8). Among other nozzle types (ST, IDK and TR), relative reduction in the impression area of a single droplet on the middle and lower part of the plant proved to be bigger than with the TWIN nozzle. There were, however, no statistically significant differences among the three above-stated nozzle types. Based on we concluded that thick canopy represents a great obstacle for the droplets on their way downwards. Furthermore, the impression area of a single droplet on the lower part of the plant is reduced to 1/3 or 1/4 of the upper part value. Impression area of a single droplet is, moreover, dependent upon the vertical distance between the nozzle and the target area. In comparison with the upper part, middle and lower parts of the plant were reached predominantly by a range of finer droplets. It is important to ensure that the difference in the size of droplets falling on the top of the plant and those reaching its lower part is not excessive. With both standard nozzle types (ST and TR), impression area of a single droplet was very small already in the middle, but even more in the lower part of the plant. These two nozzles form a range of fine and very fine droplets extremely sensitive to drift. Droplets are considered driftable if their volume median diameter (VMD) is smaller than 150 |im. According to Lešnik (2007), the nozzles which form very fine droplets (e.g. the TR nozzle) create 50-60% of driftable droplets. Nozzles forming fine droplets (e.g. the ST nozzle) have 20 to 50% driftable droplets. On the whole, flat fan air-injector nozzle IDK proved to have the best fungicide deposition quality on potato leaves at all the levels (upper, middle and lower part of the plant). This nozzle reached the highest coverage value in the middle and lower part of the plant. A sufficient number of droplets managed to penetrate the lowest parts of the plant and there was a less than 50% reduction in coverage of the lower part in comparison with the upper part. Moreover, impression area of a single droplet and subsequent droplet size were also sufficiently large. This confirmed the hypothesis that air-injector nozzle types ensure better spray deposition on potato plants. These results partially correspond to Klausen's findings (2007) of a better spray deposition with air-injector nozzles in comparison with standard nozzles. Nonetheless, our results are not directly comparable with his findings since his trial involved an air-assisted sprayer and a Danfoil sprayer, while our own included a standard sprayer. The hypothesis was only confirmed for the IDK nozzle, and not the symmetric double flat fan air-injector nozzle TWIN. The coverage value of this nozzle type was insufficient particularly in the lower part of the plant. Despite a sufficient impression area of a single droplet, droplet impression number per cm2 proved to be too small. It is assumed that spray jet angles of the TWIN nozzle (30 ° forward angle and 30 ° backward angle) are too wide, thus reducing the possibility for the droplets to penetrate the lower parts of the plant. Our findings are different to those of Knewitz and Koch (2010), Kierzek and Wachowiak (2009), and Luckhard and Brune (2011), all determining that the use of air-symmetric double flat fan injector nozzles results in a better coverage in comparison with the single spray jet air-injector nozzles. Standard ST and TR nozzles reached worse coverage values of the middle and lower part of the plant. Our results on this point are in accordance with Stangl's statement (2009) that nozzles with fine droplets are not able to sufficiently penetrate the thick canopy. Both nozzle types form relatively fine droplets which do not have sufficient velocity and enough kinetic energy to penetrate the thick canopy. Due to this fact, droplets are much more subject to drift. The ST and TR nozzles bear the most pronounced reduction in coverage value, particularly in the middle part of the plant where it dropped to 52% (ST) and 42% (TR) in comparison with the upper part value. Similar reduction occurred with the impression area of a single droplet. On the middle part of the plant, the latter decreased by 68% (ST) and 75% (TR) in comparison with the upper part value. Our results on this point do not correspond to the results of Gajtkowski et al. (2005), and Stallinga et al. (2010) who determined that, in comparison with air-injector nozzles, the use of standard nozzles results in a better spray deposition on potato plants. As anticipated, coverage value decreased, from the top towards the lower part of the plant, regardless of the nozzle type. This corresponds to the findings of Stallinga et al. (2010). Contrary to their statements, however, the droplet impression number per cm2 increased. It is assumed that this was caused due to a larger overlap of spray patterns from the adjacent nozzles and finer droplets at a 1 i^O larger vertical distance between the nozzle and the middle/lower part of the plant. Our findings are limited to the fungicide deposition, excluding the research on the biological efficacy of the fungicide in potato late blight (Phytophthora infestans L.) and early blight (Alternaria solani L.) control. Nonetheless, potato late blight and early blight infections did not occur in our trial. 4 CONCLUSION Results of the trial show the flat fan air-injector nozzle IDK achieved the best fungicide coverage of potato leaves in the upper, middle and lower part of the plant. This nozzle reached the highest spray mixture coverage value while retaining a sufficient impression area of a single droplet in the middle and lower part of the plant. Furthermore, the coverage with spray mixture applied by the nozzle dropped by 28% in the middle part of the plant and by 46% in the lower part, which is less than with other nozzle types. The IDK nozzle forms a single vertical spray jet of coarse droplets with enough velocity and kinetic energy for the droplets to penetrate the thick canopy. Results show that the angles of both spray jets of symmetric double flat fan air-injector nozzle TWIN (the 30 ° forward and the 30 ° backward angle) are excessively wide in order for the droplets to penetrate all the way to the lower parts of the plant. This nozzle did thus not confirm the proposed hypothesis. The use of both standard nozzle types resulted in a worse coverage and impression area of a single droplet despite them having the largest droplet impression number per cm2. The two standard nozzles form a larger number of fine and very fine droplets which are excessively light and do not have enough speed to penetrate all the way to the lower parts of the plant. Among these droplets, there is a large percentage of driftable droplets (< 150 |im) which are extremely sensitive to drift. Our conclusions refer to annual results. In order to confirm results as a whole, additional field trials should be performed in the years to come. Further research should involve biological efficacy of fungicides according to various nozzle types. This would give us an even clearer picture on the effect of various nozzle types and subsequent spray deposition quality on the efficacy of potato late blight (Phytophthora infestans) and early blight (Alternaria solani) control. 5 REFERENCES Agrotop, 2010. Albuz AVI-TWIN. [online] URL: http://www.agrotop.com/attachments/article/106/211 7.pdf Brune, R.A. 2011. Wasermenge perfekt abstimmen. DLZ Agrarmagazin 4: 82-85. Gajtkowski, A., Bzdega, W., Migdalska, P. 2005. Spray coverage in potatoes with low drift and air-induction nozzles. Journal of Plant Protection Research, 45, 1: 17-23. Hadživukovic, S. 1991. Statistički metodi. Novi Sad, Inštitut za ekonomiko poljoprivrede i sociologiju sela: 585 p. Kierzek, R. 2007. New solutions in the technology of protecting potatoes from diseases. Ochrona Roslin, 52, 12: 26-29. Kierzek, R., Wachowiak, M. 2007. Effect of new spray equipments on the leaf coverage of potato. Progress in Plant Protection, 47, 1: 150-154. Kierzek, R., Wachowiak, M. 2009. Effect of new spray nozzles on potato leaf coverage with working liquid. Progress in Plant Protection, 49, 3: 11451149. Klausen, N.E. 2007. Spraying technique in potato. [online] URL: http://www.danfoil.dk/pictures_org/Farm%20Test.p df Košmelj, K. 2001. Statistične metode. Delovno gradivo 2000/2001. Ljubljana, Biotehniška fakulteta: 90 p. Knewitz, H., Koch, H. 2010. Was die neuen Düsen bringen? DLG-Mitteilungen, 3: 68-71. Kryger Jensen, P. 2007. Can new spray techniques improve control of potato late blight? Status and future possibilities. [online] URL: http://130.226.173.223/lbnordic/PPT/930_950_Pete r_Kryger.pdf/ Lešnik, M. 2007. Tehnika in ekologija zatiranja plevelov. Ljubljana, Kmečki glas: 243 p. Luckhard, J., Brune, R. 2011. Kartoffel rundum schützen. Kartoffelbau 4: 18-23. Spray application technique, 2003. British potato council. [online] URL: http ://www.potato. org.uk/media_files/FAB_GAs/6s pray_technique2004.pdf Stallinga, H., van de Zande, J.C., Michielsen, J.M.G.P., Meier, R., Schepers, H.T.A.M., van Velde, P., Verwijs, B. 2010. Effect of sprayer speed and nozzle type on spray distribution and biological efficacy in potato late blight control. Aspects of Applied Biology, 99: 89-96. Stangl, J. 2009. Applikationstechnik - Wie viel Wasser und welche Düse? Die fortschrichttliche Landwirt, 19: 27-29. Strasburger, E. 1991. Lehrbuch der Botanik für Hochschulen. Stuttgart, Jena, New York, Gustav Fischer Verlag: 1030 p. COBISS Code 1.01 DOI: 10.2478/v10014-012-0016-1 Agrovoc descriptors: water balance, groundwater, lysimeters, évapotranspiration, measuring instruments, equipment, meteorological instruments, plant cover, water use, precipitation, resource management, water management, water resources, water pollution, groundwater pollution Agris category code: p10 Determination of water balance components with high precision weighing lysimeter in Kleče Vesna ZUPANC1, Reinhard NOLZ2, Peter CEPUDER2, Branka BRAČIČ - ŽELEZNIK3, Marina PINTAR1 Received August 30, 2012; accepted September 28, 2012. Delo je prispelo 30. avgusta 2012, sprejeto 28. septembra 2012. ABSTRACT Components of the basic water balance equation and water balance calculation for July 2011 for weighing lysimeter on water supply pumping station in Klece, Ljubljana the presented. Lysimeter and outflow mass measured with high precision weighing cells and precipitation as determined from changes in the mass of the lysimeter were used in calculation. Precipitation measurements in the same time resolution as the lysimeter mass measurements would be needed for correct calculation of actual evapotranspiration. In time of high plant water requirements only substantial precipitation events directly contribute to immediate groundwater recharge. The low water retention of the aquifer sediments shows susceptibility of the aquifer to ground water pollution. Key words: weighing lysimeter, water balance, lysimeter station IZVLEČEK DOLOČITEV ČLENOV VODNE BALANCE Z NATANČNIM TEHTALNIM LIZIMETROM V KLEČAH Obravnavani so členi in izračun osnovne enačbe za vodno balance za julij 2011 za tehtalni lizimeter na črpališču pitne vode Kleče v Ljubljani. Pri izračunu so bile uporabljene meritve mase lizimetra in iztoka, merjene z natačnimi tehtalnimi celicami ter padavin, izračunane iz spremembe mase lizimetra. Za pravilen izračun dejanske evapotranspiracije bi bile potrebne meritve padavin v enakem časovnem razkoraku kot potekajo meritve na tehtalnem lizimetru. V času visoke porabe vode s strani rastlinskega pokrova k bogatitvi podtalnice prispevajo le večji, zaporedni padavinski dogodki. Nizke zadrževalne sposobnosti sedimentov vodonosnika kažejo občutljivost vodonosnika in ogroženost podzemne vode zaradi onesnaženja. Ključne besede: tehtalni lizimeter, vodna bilanca, lizimetrska postaja 1 INTRODUCTION Lysimeters are used for the measurement of amount and quality of water percolation beneath plant's root zone, water loss via evapotranspiration, as well as numerous ranges of applications in agriculture and environment (Meissner et al., 2010). Quantification of soil water flow is a prerequisite for accurate prediction of solute transfer within the unsaturated zone (Meissner et al., 2010) providing answers to both scientific and practical questions regarding protection of groundwater and groundwater recharge. 1 Biotechnical faculty, p.p.2995, 1001 Ljubljana, vesna.zupanc@bf.uni-lj.si 2 Institute of Hydraulics and Rural Water Management, University of Natural Resources and Life Sciences, Vienna, Austria 2 Drinking Water and Sewerage System Public Utility, Ljubljana, Slovenia Practical application of groundwater models for urban water management can be hampered by the lack of knowledge of the complex urban groundwater recharge patterns (Vizintin et al., 2010). Groundwater from Ljubljansko polje aquifer, which is in the center of Slovenia, is fresh water source for the 270 000 inhabitants of Slovenia's capital (Vizintin et al., 2010). Above the aquifer intensive vegetable production is ongoing in close proximity to or even within the protected groundwater zone, posing a threat to groundwater quality (Zupanc et al., 2011). In the recent years lysimetry has evolved significantly and improved techniques, which enable accurate measurements of water flow and water balance parameters (Meissner et al., 2010, von Unold and Fank, 2008), and can be used for investigating hydrological processes such as precipitation, infiltration, or deep percolation with respect to groundwater recharge. In this article we address water balance for July 2011 by using data from the lysimeter station in Ljubljana Klece, and some of the challenges arising from calculation and data interpretation. 2 MATERIALS AND METHODS Lysimeter station in Ljubljana Kleče Water Pumping station was constructed in the eighties for the water balance measurements (Brilly and Gorišek, 1985), however outflow measurements indicated structural damage (Zupanc et al., 2005). In 2010 a new and technically advanced weighing lysimeter was installed at the drinking water pumping station in Ljubljana Kleče, Slovenia (308 m altitude, 46°5'11'' N, 14°29'56'' E), that enables state-of-the-art measurements of water balance parameters. The type of lysimeter is a scientific lysimeter (von Unold and Fank, 2008), designed to solve the water balance equation by measuring the mass of the lysimeter monolith as well as that of outflow tank with high accuracy and high temporal resolution. The soil monolith (2 m height, surface area 1 m2) was taken from sandy gravel sediments on the area of the water pumping station (Fluvisol), plant cover is extensive grass. The lysimeter weighing facility detects mass changes as small as 30 g, which corresponds to a water head of 0.03 mm. Inside the monolith T8 tensiometers and TDR Trime probes were installed to measure soil water status, namely soil water tension (hPa) and soil water content (%), respectively (Table 1, Figure 1). In addition, water sampling from monolith horizons under field conditions is possible to describe the solute fluxes inside the soil profile (von Unold and Fank, 2008). Figure 1 shows the structure of the lysimeter facilities (lysimeter vessel, outflow tank, pump, and data logger), and data management processes, as well as the lysimeter bottom boundary conditions subroutine. The latter is necessary in order to adapt the water dynamics inside the lysimeter as a closed system to the conditions in an undisturbed field soil profile. Outflow water is collected with suction cups and pumped into outflow storage tank. Boundary conditions are controlled through soil water status (soil water tension, Figure 1) on the bottom of the lysimeter and in the field on the same depth (190 cm). If necessary, water is pumped back into the lysimeter to maintain the same soil water status. Total water mass of the full outflow tank is 30 kg, drainage capacity is 20 kg, boundary conditions water supply 10 kg. Table 1: Hydrological quantities measured on the lysimeter station in Kleče, Ljubljana Parameter Units Time step Weighing Lysimeter Water tension - lysimeter (50, 100, 150, 190 cm) hPa 10 min 2010 Water tension - field (190 cm) hPa 10 min Water content (50, 100, 150 cm) Vol % 10 min Soil temperature - lysimeter (50, 100, 150, 190 cm) C 10 min Soil temperature - field (190 cm) C 10 min Lysimeter mass kg 1 min Outflow tank mass kg 1 min Environmental Precipitation mm 24h sum Agency of Slovenia Components of the basic water balance equation for the lysimeter are precipitation (P), outflow (O), evapotranspiration (ET) and change of water in the monolith (AS), written as P - ET - O - AS = 0 (1) If the lysimeters' mass is recorded in certain time steps, with precipitation and outflow amount measured separately, actual evapotranspiration can be deduced from their mass change (Young et al. 1996). ETa should then be calculated after ETa = (P+i - Pi) - (W1+1 - Wi) - (O+i - O), (2) where ETa is actual evapotranspiration (mm), Pi precipitation (mm), Wi lysimeter mass (kg) and Oi mass of the outflow tank (kg), i is the time step. All quantities should have the same temporal resolution. W and O were measured at the lysimeter facility in 1-minute-intervals (Table 1). P was measured on-site (Psite), and at the meteorological station of the Environmental Agency of Slovenia (ARSO) in Ljubljana (Pdty) (299 m altitude, 46°3'57'' N, 14°31'2'' E) with standard pluviograph, which gives the sum of precipitation for 24 hours (from 7 am to 7 am). Therefore ETa was determined on a daily base using Eq. 2, with i being 24hrs. Furthermore, P was determined directly from the lysimeter weighing data (Plys). Plys was calculated by first determining positive W change with the help of graph, then subtracting W immediately before mass increase from the maximum W before the latter began decreasing (which is due to either ET or O). The basic approach is that in short time intervals either P (positive mass change) or ET (negative mass change) occur, with O being taken into account (von Unold and Fank, 2008). Obviously, this method can provide only an estimation of P, because during rainfall also evaporation and transpiration take place, which can have significant influence if precipitation event is small and the surface hot. Due to high spatial variability of the storms (Barros and Lettenmeier, 1994), measurements on lysimeter's micro location is necessary. Weighing lysimeters with the same precision have given good results for dew measurements (Meissner et al., 2007, Xiao et al., 2009), and they deliver proper results if P from standardized pluviographs is not representative (remote location), malfunctioning or inadequate in terms of temporal resolution of measurements. Reference evapotranspiration (ET0) was calculated by ARSO according to FAO-Penman-Monteith (Allen et al., 1998) based on weather data from the meteorological station in Ljubljana (299 m altitude, 46°3'57'' N, 14°31'2'' E). Figure 1: Flow chart of Klece weighing lysimeter station elements and sensors, as well as data transfer and storage 3 RESULTS AND DISCUSSION Figure 2 shows the mass changes of the lysimeter monolith and the outflow tank. The mass of the lysimeter was between 4030.6 kg (minimum on the 17th of July) and 4219.9 kg (maximum on the 24th of July, Figure 2) representing a change in profile water content of about 190 mm. Outflow was about 130 mm in the same period. Based on the mass changes 15 precipitation events were determined (Figure 2, Table 2), two substantial: one on the 17th of July and a second on the 23th of July. Total monthly precipitation amount was 246.5 mm. The precipitation from 22nd to 24th of July caused high outflow - the outflow tank was emptied six times - that lasted for several days and disguised the subsequent precipitation event on the 27th of July (3.9 mm, as determined from the data). The amount of monthly outflow was about 60 % of the rainfall in July. The pluviograph on the lysimeter station delivered no data (Psite) after 23rd of July (Table 2), presumably malfunction occurred due to high intensity of the event. Namely, precipitation event on the 23rd of July begun at 20:17 (W = 4076.6 kg, Figure 2) and lasted until 22:09 (W = 4134.77 kg, Figure 2) with high intensity (31.1 mmh-1) that was observed for example in precipitation events in Julian Alps (Žagar et al., 2004), then after a short break continued until the next day at 8:08 (Wmax = 4219.9 kg) with lower intensity (8.5 mm h-1) (Figure 2). Measurements from the ARSO meteorological station (Pcity) were significantly different, thus they were not representative. Consequently, calculated using Plys. actual ETa was The first half of July was hot and dry with an average ET0 of 5.4 mm per day. In the same period, ETa was always lower with an average of 4.5 mm per day (Table 2). An explanation for the differences is that ET0 was calculated using data from the ARSO meteorological station in the city (ca. 4 km away), and micro climatic conditions of the Kleče lysimeter station differ due to the surrounding forrest. It is also possible that the differences between calculated ET0 and measured ETa are that the grass cover does not fulfill the requirements for comparing Penman-Monteith calculation (Allen et al., 2011). The second half was affected from several rainfall events as mentioned before. ETa exceeded ET0 after rainfall, likely due to interception and evaporation losses. On 23rd and 24th the water balance resulted in improper negative ETa. This problem should be solved by optimizing interpretation of outflow data, especially at high outflow rates with several emptying processes of the outflow tank. Lysimeter mass (kg) Outflow tank mass (kg) 250 J precipitation ~~ event — — Lysimeter mass (kg) — Outflow tan k m ass (kg) 1 ii A i \ 1 \ I ; \ \ 1 1 1 1 / I i / — 1 r — i —- ,J - J / ) j —-- --- 12.7.11 14.7.11 17.7.11 20.7.11 23.7.11 25.7.11 28.7.11 31.7.11 Figure 2: Mass of lysimeter (kg) and outflow tank (kg) for lysimeter station in Kleče in July 2011, black arrows mark precipitation events Table 2: Water balance parameters: mass change of lysimeter dW7h and outflow tank dO7h, precipitation measured by ARSO in the city Pcity and on the site Psite, and Plys as determined from W data, ET0 and ETa calculated from Eq. 2 using Plys Date dW7h (mm) dO7h (mm) Pcly (mm) Ps,te (mm) Pivs (mm) ET0 (mm) ETa (mm) 1.7.2011 1.3 1.7 5.8 3.8 2.9 2.7.2011 -4.5 0.6 4.2 5.6 4.1 3.9 3.7.2011 -5.9 1.5 5.1 4.5 4.7.2011 -7.9 2.5 5.9 5.4 5.7.2011 3.2 1.3 8.0 4.2 3.4 6.7.2011 -5.5 0.9 10.3 7.4 0.2 5.0 4.8 7.7.2011 -5.9 0.8 5.8 5.0 8.7.2011 -6.0 0.7 0.1 6.2 5.4 9.7.2011 -6.0 0.8 6.2 5.2 10.7.2011 -5.9 0.7 6.5 5.2 11.7.2011 -5.2 0.5 6.1 4.8 12.7.2011 -4.8 0.7 5.4 4.1 13.7.2011 -4.9 0.3 5.7 4.6 14.7.2011 -4.7 0.4 5.9 4.3 15.7.2011 7.3 0.4 10.3 3.0 2.6 16.7.2011 -4.3 0.4 7.4 7.8 4.3 4.0 17.7.2011 27.1 0.2 31.0 5.2 3.7 18.7.2011 3.9 0.4 21.8 28.0 6.8 3.9 2.5 19.7.2011 -2.0 0.2 4.5 6.6 4.0 1.7 20.7.2011 4.3 0.2 1.3 1.8 8.9 3.5 4.4 21.7.2011 -6.2 0.4 6.5 6.6 5.5 5.8 22.7.2011 13.1 0.3 17.6 4.7 4.1 23.7.2011 140.9 2.9 20.2 - 143.8 2.4 0.0 24.7.2011 -57.4 64.4 65.5 - 4.7 1.7 -2.3 25.7.2011 -35.5 32.2 7.8 - 2.1 3.3 26.7.2011 -8.9 5.0 - 3.4 3.9 27.7.2011 -2.7 3.1 - 3.9 4.6 3.5 28.7.2011 -3.0 2.0 5.2 - 0.5 2.3 1.4 29.7.2011 -2.4 1.4 0.5 - 2.3 3.6 3.3 30.7.2011 -1.0 1.4 0.8 - 2.6 3.3 2.1 31.7.2011 -4.7 0.9 1.2 - 3.4 3.9 Sum 5.8 -129.1 157.2 * 246.5 136.8 111.5 Sensors for monitoring water status inside the lysimeter showed high soil water content (SWC) in 50 and 100 cm depth (Figure 3). SWC in 50 cm decreased slightly until rainfall from 22nd onwards. Neither previous rainfall events nor characteristics of plant water uptake - usually expressed as stepwise decrease of SWC representing typical day-night-effects -were displayed. It can be concluded that higher soil water dynamics occurred in the upper soil layer and the rooting zone, respectively. Decrease of SWC in 50 cm can be explained by water movement to upper soil layers compensating ET losses, or water flow to deeper layers, mainly due to gravitation forces. This question cannot be explained satisfactorily without information on water potential in the respective soil layers. SWC in 100 and 150 cm did not change visibly until rainfall from 22nd onwards (Figure 3), however, downward water fluxes must be assumed, because of the constant outflow at the bottom boundary (Figure 2). Low SWC (between 6 and 9 %) of the 150 cm layer indicates poor water retention capacity (Figure 3), typical for gravely soils found on Ljubljana aquifer (Vizintin et al., 2009). The spike in SWC after 24th of July for 36 hrs represented water from rainfall moving towards outflow. Measurements of the soil water tension in 190 cm depth inside the lysimeter and in the field (Figure 4) showed unsaturated conditions in the lysimeter and in the field (between -9 and -20 hPa). During high precipitation between 22nd and 24th of July the outflow through the suction cups at the bottom of the lysimeter was not sufficiently fast to match the flow of the water through the soil layers outside in the field conditions, causing temporary water logging of the lower layers, expressed as positive water pressure 25 hPa in the lysimeter (Figure 4). Water pressure in 190 cm in the field remained negative (-3 hPa, Figure 4), indicating that the water flow following the storm did not saturate the lower layers but has moved through the gravelly sediments in a few hours. Figure 3: Soil water content (%) in three soil depths (50, 100 and 150 cm) inside the Kleče lysimeter measured by TDR-probes in July 2011 Figure 4: Soil water tension (hPa) in 190 cm depth conditions management in July 2011 Only short period was evaluated, however the chosen month demonstrates weather extremes of the local climate - relatively dry periods, followed by high precipitation amount. In time of high plant water requirements only subsequent substantial precipitation events directly results in water flow towards lower layers. At the same time, the stony, gravelly layers of the deeper parts of the sediments have little or no capacity for water retention, inside the Klece lysimeter and in the field for boundary and in the event that water line leaves top soil, water flow moves downwards fairly quickly. On one hand this confirms high recharge capacity of Ljubljansko polje aquifer from precipitation (Vizintin et al., 2009) on green areas; on the other hand it shows tremendous susceptibility of the aquifer to pollution and reinforces the position of groundwater protection zones above aquifer. 4 CONCLUSIONS Practical execution of the commonly applied water balance equation is not as straightforward. Precipitation measurement in the same time resolution as the lysimeter mass measurements is needed for correct calculation of reference evapotranspiration. It is also possible that the outflow rate, which is determined by water flow through suction cups by pump activity, should be re-set. The results show that in time of high plant water requirements only substantial precipitation events directly contribute to immediate groundwater recharge as well as susceptibility of the aquifer of Ljubjansko polje to ground water pollution. 5 ACKNOWLEDGEMENTS Authors thank the reviewers for their constructive remarks, which helped improve the quality of the manuscript. This work was partly funded by Austrian agency for international mobility and cooperation in education, science and research (OeAD) and Slovenian Research Agency in bilateral cooperation project BI-AT 11-12-024 - Comparison of data management for selected lysimeter stations in Slovenia and Austria. 6 REFERENCES Allen R.G., Pereira L.S., Raes D., Smith, M. 1998. Crop Evapotranspiration: Guidelines for computing crop water requirements. Irrigation and Drainage Paper 56, Food and Agriculture Organization of the United Nations, Rome, 300 p. Allen R.G., Pereira L.S., Howell T.A., Jensen M.E. 2011. Evapotranspiration information reporting: I. Factors governing measurement Accuracy: review. Agricultural Water Management, 98: 899-920 Barros A.P., Lettenmaier D.P. 1994. Dynamic modeling of orographically induced precipitation. Reviews of geophysics, 32 (3): 265-284 Brilly M., Gorišek M 1985: Matematični model podtalnice Ljubljanskega barja : II. faza raziskave podtalne vode na Ljubljanskem barju, Ljubljana: FAGG, Laboratorij za mehaniko tekočin (in Slovenian) Meissner R., Seeger J., Rupp H. 1998. Lysimeter studies in East Germany concerning the influence of set aside of intensively farmed land on the seepage water quality. Agriculture, Ecosystems and Environment, 67: 161-173 Meissner R., Seeger J., Rupp H., Seyfarth M., Borg H. 2007. Measurement of dew, fog, and rime with a high precision gravitation Lysimeter. Journal of Plant Nutrition and Soil Science, 170, 335-344 Vižintin G., Souvent P., Veselič M., Cencur Curk B. 2009. Determination of urban groundwater pollution in alluvial aquifer using linked process models considering urban water cycle. Journal of Hydrology, 377, 3-4: 261-273 Von Unold G., Fank J. 2008. Modular Design of Field Lysimeters for Specific Application Needs. Water Air Soil Pollut: Focus 8: 233-242 Xiao H., Meissner R., Seeger J., Rupp H., Borg H. 2009. Effect of vegetation type and growth stage on dewfall, determined with high precision weighing lysimeters at a site in northern Germany. Journal of Hydrology 377: 43-49 Young M.H., Wierenga P.J., Mancino C.F. 1996. Large weighing lysimeters for water use and deep percolation studies. Soil Science, 161: 491-501 Zupanc V., Bračič-Železnik B., Pintar M. 2005. Water balance assessment for lysimeter station based on Water Pumping Station Kleče in Ljubljana. Acta agric. Slov.. 85 (1), 83-90. Zupanc V., Šturm M., Lojen S., Maršic-Kacjan N., Adu-Gyamfi J., Bračič-Železnik B., Urbanc J., Pintar M. 2011. Nitrate leaching under vegetable field above a shallow aquifer in Slovenia. Agriculture, Ecosystems & Environment, 144, 1: 167-174 Žagar M., Pristov N., Rakovec J. 2004. A diagnostic method for high-resolution precipitation prediction using dynamically adapted vertical velocities. Meteorol Atmos Phys 85, 187-204 COBISS Code 1.01 Agrovoc descriptors: agriculture, developing countries, appropriate technology, information processing, data collection, data processing, information services, information technology, information systems, communication technology, social change, socioeconomic development, education, extension activities, adult education, advisory officers Agris category code: a01, c20, c30 E-readiness of Rural ICT Offices for Rice e-marketing in Rasht Township, Iran Seyed Jaber ALAVION1, Mohammad Sadegh ALLAHYARI2* Received November 6, 2011; accepted March 28, 2012. Delo je prispelo 6. novembra 2011, sprejeto 28. marca 2012. ABSTRACT Applying Information and Communication Technology (ICT) in different economic sectors, especially the agricultural sector is increasing in developing countries. Rural ICT offices in Iran have an important role in decreasing the digital divide by representing internet, post and bank services; however they are not yet active in agricultural services. The present study seeks to survey the electronic readiness of 68 rural ICT offices in the rural area of Rasht in Guilan province, in the northern part of Iran. A five-point Likert type scale questionnaire was prepared, to survey socio-cultural, legal, connection and backup services indices. Results indicated that intention to adopt, and legal aspects, required development, but the socio-cultural index had a better situation in comparison with others, and receptivity to agricultural electronic commerce (e-commerce) showed a high percentage among respondents. So this points to the necessity of creating an integrated website for rural offices to represent agricultural services. Also, the level of education and age of managers did not show any significant influence on receptivity to e-commerce, but internet skills and farmers visiting the offices have been important factors in receptivity to e-commerce. Key words: E-readiness, rural ICT offices, e-marketing, Rasht IZVLEČEK PRIPRAVLJENOST PODEŽELSKIH IKT SVETOVALCEV ZA E-MARKETING RIŽA NA OBMOČJU MESTA RASHT, IRAN Uporaba informacijske in komunikacijske tehnologije (IKT) v različnih gospodarskih sektorjih, še posebej v kmetijstvu, se v državah v razvoju stalno povečuje. Podeželski IKT svetovalci imajo v Iranu pomembno vlogo v zmanjševanju digitalne pregrade tako, da posredujejo internetne, poštne in bančne usluge, niso pa še aktivni pri posredovanju elektronskih uslug za kmetijstvo. Predstavljena študija želi preučiti pripravljenost 68 podeželskih IKT svetovalcev v območju provinc Rasht in Guilan v severnem Iranu. Pripravljen je bil vprašalnik s petstopenjsko Likertovo lestvico s katerim smo ocenjevali kulturno-sociološke, pravne, povezovalne in podporne storitvene kazalnike. Rezultati kažejo, da namen za sprejetje storitev in pravna vprašanja zahtevajo dodatni razvoj, medtem ko imajo kulturno- socialni kazalniki, v primerjavi z ostalimi, višje vrednosti, kar velja tudi za sprejemljivost elektronsko trgovanje v kmetijstvu. To nakazuje potrebo po oblikovanju celovite spletne storitve za kmetijstvo, ki jo bodo podeželski svetovalci lahko uporabljali. Stopnja izobrazbe in starost podeželskih svetovalcev ni pokazala nobenega statistično značilnega vpliva na njihovo pripravljenost za elektronsko trgovanje, obratno pa velja za poznavanje interneta in pogostnost obiskov kmetov. Ključne besede: E-pripravljenost, podeželski IKT svetovalci, e-marketing, Rasht 1 Young Researchers Club, Rasht Branch, Islamic Azad University, Rasht, Iran 2* Department of Agricultural Management, Rasht Branch, Islamic Azad University, Rasht, Iran, allahyari@iaurasht.ac.ir, corresponding author 1 INTRODUCTION The world has witnessed the birth of a new era - the information age, a global wave sweeping through all corners of the world (Ifinedo, 2005). Information and Communication Technology (ICT) consists of some latest technologies such as the computer, internet, cell phone and satellite. Older technologies like radio, television, telephone and technology centers, employers, and investment are also in this zone (Dada, 2006, ITU, 2010). E-readiness (electronic readiness) assesses the quality of a country's ICT infrastructure and the ability of its consumers, businesses and governments to use ICT to their benefit. According to APEC (1999) e-readiness is the degree to which an economy or community is prepared to participate in the digital economy. McConnell International (2000) defines e-readiness as the capacity to participate in the global digital economy. In 2010, e-readiness was renamed as the digital economy (EIU, 2010). In 2006 a study attempted to critically assess the concept of e-readiness (electronic readiness), and suggest ways to bridge the limitation of this tool, with a special focus on developing countries. Results showed that there were both positive and negative aspects of such measures. It was discovered that although e-readiness measures provide a useful overview of the environmental situation, they do not completely reflect the possibility of achieving development from ICT in developing countries. However, there are implications for further research in this area (Dada, 2006). Ramayah et al. (2005) studied SME e-readiness in Malaysia. They reported that SMEs in Northern Malaysia are ready to go for e-business, e-commerce and Internet in general. They also showed that in general top management commitment and infrastructure and technology have significant impact on SMEs' e-readiness. However, human capital, resistance to change, and information security do not have significant impact or contribution on e-readiness in SMEs. The government of Zimbabwe commissioned an e-readiness survey in 2005 in conjunction with the National Economic Consultative Forum (NECF) to assess the country's readiness to embrace ICT. Such findings will later inform a broader national policy. However it does not explain whether in the absence of a national ICT policy, there were sector specific policies, as having such a policy is imperative. In order to bridge the digital gap, Zimbabwe needs to build the infrastructure to allow ICT to be accessible. There is a need to consider non-quantifiable variables, such as poverty and social justice. The other factor is the need for Zimbabwe's government to address current political and economic problems, as this isolation would impact heavily on the need to be interconnected (Mhlanga, 2006). In a survey about digital development of rural areas in the USA, Maleki (2003) noted that Information Technology (IT) could be very efficient. However this efficiency is based on two factors which do not usually exist in rural sections-economies of scale and end-to-end service capability. He mentioned that investment in infrastructure would be the first step, and rural areas have been less considered in this issue. Not only investing in communication systems is important for rural development, but also educating villagers and local leaders. Information technology could develop rural business, and could be effective in job-creation (Maleki, 2003). Case study evidence from various developing countries suggests that use of ICTs -especially mobile phones - is increasing among rural enterprises, and makes a positive contribution to enterprise growth in rural areas. In the case of small farmers, diverse information needs can be identified along the value chain in connection with their primary and support activities; - Inbound logistics - information concerning the sourcing and purchasing of seeds for a specific crop. - Operations - information concerning seeding, preparing, planting, growing and harvesting. - Marketing and sales - information that helps identify customers for the output. It is also important for the farmer to know when, and in which, markets to buy and sell. - Outbound logistics - information concerning packaging, storing and transport. - After-sales service - feedback from customers. - Support activities - information on access to extension services, credit and insurance. Information needs in rural enterprises directly linked to the poor can be considerable. A study of the value chain of poor vegetable farmers in Sri Lanka measured the information search costs for all core enterprise operations, such as land preparation, growing and harvesting, as well as for seed purchase and selling. It found that the relative proportion of information search costs in the total costs of production were highest in the early decision stages and the latter selling stages. Overall, information search costs amounted to 70 per cent of all transaction costs, and the transaction costs themselves were recorded as fifteen per cent of the total costs incurred. There is growing evidence that enhanced access to ICT has helped farmers address some or all of these needs. In many instances, this has been achieved through the spontaneous uptake of mobiles by farmers; in other cases information supply has improved as a result of deliberate assistance by government or other actors. There are also many examples of ICT initiatives aimed at improving relevant information that have failed to produce the desired results (UNCTAD, 2010). In 2004 a study was conducted to evaluate the e-readiness of non-profit organizations (NPOs) in the Western Cape. The assessment of 100 NPOs, spread throughout the province, helped to identify the constraints to greater ICT adoption among NPOs, and also to determine if geographic location - inside or outside the City of Cape Town Municipality - has an influence on NPO e-readiness. Based on the results of the survey, appropriate recommendations were made to the government for its ICT enablement programs (Vosloo and Paul, 2004). The Hawaii Department of Agriculture in a study called, "the feasibility of a farmer based e-commerce market", studied factors such as farmers' computer skills, internet structure and the way of delivering the product to the market, and then a website was designed. Farmers could deliver products to farm businesses, and then a central company would deliver the products to the customer (Hawaii Department of Agriculture., 2006). FAO reported some examples of using rural ICT at different countries, in a report named 'Electronic Agriculture'. Egypt VERCON (Virtual Extension and Research Communication Network) -Government researchers and extension workers in institutes and rural villages are now actively using a web-based portal system to exchange critical information with district offices and Ministries in Cairo. Researchers and extension workers presently access information resources such as extension brochures, statistical databases, decision support systems, and can participate in special interest forums, online discussions, news and events. An online query system called 'Farmer's Problems' answers technical questions raised by smallholder farmers. FoodNet - This network in Uganda comprises a national system that was established to gather and disseminate agricultural market price information via newspapers, the Internet, radio and mobile phones (SMS). FoodNet is a typical example of an agriculture application that can be found in many countries, showing how small-scale farmers in rural communities can overcome their marginalization through a mix of media including ICT based information access. Rural Radio, ICTs and Food Security - for billions of people in rural areas, where illiteracy rates are high and access to electricity, phones and Internet is marginal to say the least, radio is still the most accessible, economical, and popular means of communication. FAO is working with the World Association of Community Broadcasters, AMARC, an international community radio network, and the Developing Countries' Farm Radio Network (DCFRN) to enhance networking and sharing by assisting radio stations to use the Internet to access alternative information on a range of subjects of interest to rural communities, including health, education, credit and local projects (FAO, 2005). Establishment of rural ICT offices in Iran began in 2004 in villages with more than 150 families, and it developed from 963 rural offices in 2005, to 10,000 offices in 2010. Agriculture has the highest percentage of employment in Guilan province. It seems necessary to use the capacities of rural ICT offices to help with agricultural activities. The number of villages in Guilan province is more than 2600, of which 533 villages are equipped with ICT offices. Also the Rasht Township area has 292 villages, of which 92 have rural ICT offices. These offices have concentrated on areas of internet services, bank services and postal services in villages (Iran Statistics Centre, 2010). The main purpose of this study was to determine the e-readiness of rural ICT offices for rice e-marketing in Rasht Township, Iran. For this the following objectives were considered: 1 - Identifying the e-readiness of rural ICT offices. 2 - Identifying the effective factors in adoption of electronic marketing. 3 - Identifying attitudes of ICT office managers toward agricultural e-marketing. 4 - Identifying attitudes of ICT office managers about the e-marketing network. 2 MATERIALS AND METHODS The Rasht Township is located in the north of Iran in Guilan Province and has six urban districts (the hachured areas in Figure 1). At the time of this study, 24 rural ICT offices among 92 offices were not active, and 68 offices rendered services which are shown in black points on the map. All 68 offices were interviewed. As can be observed, these offices have a wide dispersion in the area of villages. Establishment of these offices has simplified accessibility to communication services for villagers, so decreasing their traffic to urban areas. The researchers used survey research methods in which data was gathered by the questionnaire. Respondents were selected from rural ITCs offices in Rasht Township. Distributing 68 questionnaires related to rural ICT management was achieved in three forms; thirty-five offices by fax, 22 offices by e-mail, and eleven offices by post. Before the questionnaires were sent, managers were called by phone and some details about the purpose of the survey were offered. To determine the validity of the questionnaire, ICT experts' comments were used. To measure questionnaire reliability, ten of them were distributed to rural ICT offices, which were randomly selected, and finally, its reliability was established at 0.83, through the use of Cronbach's alpha coefficient. Data were collected from February to May, 2011, and coded and entered onto an Excel spreadsheet, imported into a PASW Statistics 18 data file, and analyzed using PASW Statistics 18. Calculations were of frequencies, percentages, means, standard deviations, cross-tabulations, Kurskal-Wallis test, and correlations. 3 RESULTS Table 1 shows that among managers of ICT families were engaged in agricultural offices, most (60.3 per cent) were aged activities. between 20 to 30. More than 70 per cent of Table 1: Personal characteristics Age: frequencies percent 20 - 30 41 60.3 31 - 40 19 27.9 41 - 50 6 8.9 <51 2 2.9 Farmer family: Yes 49 72.1 No 19 27.9 Level of education: High school diploma 26 38.2 2 years college 17 25.0 Bachelor's degree 25 36.8 3.1 Identifying the level of e-readiness of rural ICT offices To identify the level of e-readiness of rural ICT offices in Rasht Township, three indices with six questions in 5-point Likert type were asked from ICT officers. In the socio-cultural index and in the sub-index of adoption of electronic marketing, 77.9 per cent of managers had a good and very good tendency to cooperate with electronic marketing. Even in the sub-index of Internet skills, the condition was acceptable, and more than 50 per cent of managers reported 'good' and 'very good' status for their internet skills (table 2). Also, about level of education as a sub index of socio-cultural index, 38 per cent held a high school diploma, and 62 per cent held an academic degree (table 1). Regarding the legal index related to electronic commerce and banking which was asked respondents to show their answers regarding the level of current laws to support e-marketing, 45.6 per cent of respondents reported at 'moderate' level and 23.5 per cent reported at 'good' situation. In the back-up services index there was three sub indices. In the sub-index of e-banking education, 44 per cent of ICT offices managers reported an 'average' education. In post services, 69 per cent reported a condition between 'moderate' to 'good' situation. In addition, half of respondents reported a 'moderate' to 'good' condition for technical services (table 2). Table 2: Socio-cultural, Legal, Backup services index Sub index Very good Good Moderate Weak Very weak M SD Adoption frequencies 20 33 11 1 3 3.97 0.96 Socio- cultural percent 29.4 48.5 16.2 1.5 4.4 Internet skill frequencies 10 27 26 4 1 3.60 0.86 percent 14.7 39.7 38.2 5.9 1.5 Legal e-commerce legal frequencies 1 16 31 19 1 2.95 0.79 percent 1.5 23.5 45.6 27.9 1.5 E-banking education frequencies 2 7 30 20 9 3.58 0.94 Backup services percent 2.9 10.3 44.1 29.4 13.2 Post services frequencies 9 20 27 9 3 3.33 1.01 percent 13.2 29.4 39.7 13.2 4.4 Technical services frequencies 3 8 29 20 8 2.64 0.94 percent 4.4 11.8 42.6 29.4 11.8 Most offices have ADSL broadband internet, Also, approximately 90% of offices are and bandwidth in 50% of offices is 64 kb/s. connected to a banking network (table 3). Table 3: connectivity Index Variable Internet: frequencies percent DIAL UP 10 14.9 Connectivity ADSL WIMAX 56 1 83.6 1.5 Bandwidth: 64 Kb/s 128 Kb/s 256 Kb/s 33 24 8 50.8 36.9 12.3 Banking Network: Yes No 61 7 89.7 10.3 3.2 Identifying the effective factors in receptivity to electronic marketing Age, level of education and e-banking education of ICT officers had no effect on receptivity to e-marketing, but three factors had effects on receptivity. These were, 'experience in offering internet services to farmers' (p = 0.04), 'internet skill' (p = 0.01) and 'connectivity' (p = 0.04) (table 4). Table 4: The Kurskal Wallis test - effective factors in receptivity to e-marketing Factors Chi-Square df /»-value Level of education 4.31 3 0.22 Age 4.04 3 0.25 Internet skill 12.28 4 0.01 * Experience in offering internet services to farmers 15.64 4 0.04 * E-banking education 2.45 4 0.65 Connectivity 15.24 4 0.04 * 3.3 Identifying Attitudes of ICT Office Managers towards Agricultural e-marketing Managers of ICT offices believe that agricultural e-marketing may have the most efficiency to decrease the role of the middleman. However, the option 'price Table 5: Identifying agricultural e-marketing reduction' had the least mean among respondents (M = 3.58, SD = 0.88). The score for option 'very weak' was one, and the score for option 'very good' was five. The mean of 68 managers' response for each question is represented in the table 5. Role of E-marketing in Very good Good Moderate Weak Very weak M SD Middleman decrease frequencies 23 36 7 2 G 4.17 G.73 percent 33.8 52.9 1G.3 2.9 G Ease in acquisition frequencies 29 25 11 3 G 4.17 G.86 percent 42.6 36.8 16.2 4.4 G Sale increase frequencies 22 35 1G 1 G 4.14 G.71 percent 32.4 51.5 14.6 1.5 G Demand increase frequencies 17 35 13 3 G 3.97 G.79 percent 25 51.5 19.1 4.4 G Price reduction frequencies 9 29 25 3 2 3.58 G.88 percent 13.2 42.6 36.8 4.4 2.9 3.4 Identifying Attitudes of ICT Offices Managers to the e-marketing network Table 6 shows that 70.6% of respondents choose rural ICT offices for agricultural e- Table 6: Agricultural e-marketing network marketing as the best among three possible networks, including public offices network, rural offices network and rural cooperatives network. Network frequencies percent Public offices network 2 2.9 Rural ICT offices network 48 70.6 Rural cooperatives network 18 26.5 4 DISCUSSION AND CONCLUSION Conclusions of some studies have shown that awareness and receptivity to electronic agriculture enjoys a better condition in Asia in comparison to Europe/North America. EAWG, loi or the e-agriculture Working Group (2007) studied 4000 people in 135 countries worldwide, in cooperation with FAO and several other world organizations in a poll titled, 'Familiarity with the term e-agriculture'. In a question related to respondents' familiarity with electronic agriculture in Asia, the percentage of those who were familiar with e-agriculture was more than in other continents, as 37 per cent of responses were positive. However in North America 29 per cent and in Europe 32 per cent of answers were positive. Shehata et al. (2006) interviewed 147 managers of cooperatives in a study of feasibility assessment for cooperative e-commerce. Conclusions of the polls showed that approximately 46 per cent are interested in e-commerce (Shehata, 2006), while receptivity to e-commerce was 80 per cent in this study. Postal service for the fast sending of goods from rural offices to other areas has a moderate status, while e-marketing required postal services with minimum time. Twelve per cent of rural offices have a fast internet speed (256Kb/s), 37 per cent of them have an acceptable internet speed, (128Kb/s), but 51 per cent need to develop their internet speed (64Kb/s) to begin e-commerce. At the present time, rural ICT are managed with a proper dispersion in areas of villages by personnel who are from farming families and have a suitable capacity to help agricultural activities through internet, post and bank services. It is considered necessary to create an integrated system of rural ICT offices. Rural ICT offices network could be a proper pattern in this regard. Farmers should refer to ICT offices where they live and represent specification of their products so that office operators register the information after they enter the rural office site. They would send products through that office and the post after customer purchase and receiving orders. 5 REFERENCES APEC, 1999. SME electronic commerce study (tel09/97t) final report, September 24. Dada, D. 2006. E-readiness for developing countries: moving the focus from the environment to the users. The Electronic Journal of Information Systems in Developing Countries, 27(6): 1-14. EAWG, 2007. Analysis of global e-agriculture survey. Retrieved from http://www.itu.int EIU, 2010. Digital economy rankings: beyond e-readiness. Retrieved from http://www.eiu.com FAO, 2005. E-agriculture, a definition and profile of its application, bridging the rural digital divide, Retrieved from http://www.fao.org Hawaii Department of Agriculture, 2006. Feasibility of a farmer based e-commerce market in the state of Hawaii. Retrieved from http://www.ams.usda.gov Ifinedo, P. 2005. Measuring Africa's e-readiness in the global networked economy: a nine-country data analysis. International Journal of Education and Development using Information and Communication Technology, 1(1): 53-71. ITU, 2010. Measuring the information society. Retrieved from http://www.itu.int McConnell International, 2000. Risk e-business: seize the opportunity of global e-readiness. [Online] Available: http://www.mcconnellinternational.com/ereadiness/ EreadinessReport.htm Malecki, E. 2003. Digital development in rural areas: potentials and pitfalls. Journal of Rural Studies, 19:201-214. Mhlanga, B. 2006. Information and communication technologies (ICTs) policy for change and the mask for development: a critical analysis of Zimbabwe's e-readiness survey report. The Electronic Journal of Information Systems in Developing Countries, 28(1): 1-16. Ramayah,T., Lim, C.Y. & Mohamad, S. 2005. SME e-readiness in Malaysia: implications for planning and implementation, Sasin Journal of Management, 11(1):103-120. Shehata, S., Cox, L., and Connell, T. 2006. Feasibility assessment for an E-commerce cooperative to market Hawaii's agricultural products. Retrieved from http://www.hawaiianagriculturalproducts.com UNCTAD, 2010. Information Economy Report. Retrieved from http://www.unctad.com Vosloo, S. and Paul, J. 2004. E-Government and the e-readiness of non-profit organizations in the Western Cape, South Africa, Retrieved from http:www.commerce.uct.ac.za COBISS Code 1.03 Agrovoc descriptors: citrus sinensis, sweet oranges, fruit crops, culture media, embryonic development, seedlings, regeneration, callus, nucleus, fruit, plant growth substances, maturation, plant embryos, plant developmental stages, growing media Agris category code: f62 Somatic embryogenesis and plantlet regeneration from nucleus tissues of Local orange (Citrus sinensis (L.) Osbeck) Huda Abdel-karim Al-TAHA, Abbas Mehdi JASIM and Muayed Fadhil ABBAS1 Received February 13, 2012; accepted July 23, 2012. Delo je prispelo 13. februarja 2012, sprejeto 23. julija 2011. ABSTRACT Somatic embryogenesis and plantlet regeneration were achieved in callus cultures of nucellus tissues derived from undeveloped ovules of immature fruits of local orange (Citrus sinensis (L.) Osbeck). Four types of culture media were used and all produced embryogenic callus. Somatic embryos were developed on MS medium supplemented with BA only. Embryo maturation took place on MS medium supplemented with BA and 2,4-D. Plantlets were regenerated from those somatic embryos on half strength MS medium free of plant growth regulators. The well-developed plantlets were transferred to a potting mix containing sand and peat moss (2: 1) and grown for 8 months, with a survival rate of 100 %. Abbreviation: BA: 6-benzyl amino purine; 2,4-D: 2,4-dichlorophenoxy acetic acid; NAA: a-naphthalene acetic acid Key words: citrus sinensis, embryogenic callus, somatic embryogenesis, nucleus tissues, plantlet regeneration IZVLEČEK SOMATSKA EMBRIOGENEZA IN REGENERACIJA IZ NUCELARNEGA TKIVA LOKALNE POMARANČE (Citrus sinensis (L.) Osbeck) Somatska embriogeneza in regeneracija je bila dobljena iz kalusne kulture nucelarnega tkiva pridobljenega iz nerazvitih semenskih zasnov nezrelih plodov lokalne pomaranče (Citrus sinensis (L.) Osbeck). Uporabljena so bila štiri gojišča in na vseh je nastal embriogeni kalus. Somatski embriji so se razvili na MS gojišču obogatenim samo z BA. Razviti embriji so bili prestavljeni na MS gojišče z dodatkom BA in 2,4-D. Rastline so nastale iz vseh somatskih embrijev na polovičnem MS gojišču brez rastlinskih hormonov. Dobro razvite rastline so bile prestavljene v mešanico substrata, ki je vsebovala pesek in šoto (2 : 1) in 8 mesečno rast so 100 % preživele. Kratice: BA: 6-benzil amino purin; 2,4-D: 2,4-diklorofenoksi ocetna kislina; NAA: a-naftalen ocetna kislina Ključne besede: Citrus sinensis, embriogeni kalus, somatska embriogeneza, nucelarno tkivo, regeneracija 1 College of Agriculture, Basrah UniversityBasrah, Iraq, corresponding author : muayedfadhil@yahoo.co.uk 1 INTRODUCTION Citrus is an important fruit crop worldwide. Although selected genotypes can be multiplied through grafting and budding methods, however, the rate of multiplication is very low. Thus, to meet the demands of planting materials, it is necessary to develop a suitable protocol for mass propagation from existing elite cultivars. Somatic embryogenesis is an efficient method of plant regeneration allowing rapid production of large number of plants within short period. So far, no information is available on somatic embryogenesis in local orange (Citrus sinensis (L.) Osbeck), which is the most widely grown citrus crop in Iraq. Successful somatic embryogenesis from nucellus tissues of different citrus species was achieved by several authors (Rangan et al., 1968; Chen et al, 1990; Miah et al, 2002). The present investigation was undertaken to develop the in vitro suitable protocol for micropropagation of local orange (Citrus sinensis (L.) Osbeck) from nucellus tissues through somatic embryogenesis. 2 MATERIALS AND METHODS The experiment to be described was carried out at Plant Tissue Culture Laboratories, Date Palm Research Centre, Basrah University, Basrah, Iraq. Source of plant material: Mature trees of local orange (Citrus sinensis (L.) Osbeck), grown in a private orchard were used as the source of the plant material. Preparation of explants: Immature fruits (8 weeks old after anthesis) were washed thoroughly under running tap water to reduce dust and surface contaminants. Then, they were surface disinfected by immersion in 70 % (v/v) ethanol for five minutes, then soaked for 10 minutes in 20 % commercial chlorax solution containing 1.05 % sodium hypochlorite, and finally rinsed 5 times with sterilized distilled water. The fruits were then cut open under aseptic conditions, and immature seeds were separated. For somatic embryogenic callus induction, the immature seeds were cut by a scalpel and nucellus halves were separated as described by Juarez and Navarro (1977). The nucellus tissues were then kept in an anti- oxidant solution containing 100 mg l-1 ascorbic acid and 150 mg l-1 citric acid for 24 hrs. The nucellus tissues were afterwards rinsed in sterilized water for 5 times, and then surface sterilized with 20 % commercial chlorax solution containing 1.05 % sodium hypochlorite and a drop of tween 20 for 15 minutes. The nucellus tissues, were then rinsed in sterile distilled water 3 times. Callus induction: Nucellus tissues (Fig. 1a) were cultured on four culture media, basically all contained MS salts and vitamins (Murashige and Skoog, 1962). The first medium, called M1 consisted of MS medium supplemented with 500 mg l-1 malt extract. At the same time, nucellus tissues were cultured on MS + 5.0 mg l-1 NAA + 1.0 mg l-1 BA (M2), MS + 5.0 mg l^ 2,4-D + 1.0 mg l-1 BA (m3) MS + 1.0 mg l-1 2,4-D + 5.0 mg l-1 BA (M4). The nucellus halves were incubated in conical flasks containing five samples, and five replicates for each medium. The flasks were incubated in darkness, in a growth chamber (25±2 °C) for four weeks. Formation of the primary callus: The primary callus was formed on all nucellus tissues in all media. This callus was then divided and incubated on two growth media (M2 and M3), containing half strength of MS medium for callus proliferation. The process of primary callus proliferation continued for 12 weeks, with sub-culturing every 4 weeks (Fig. 1b). Embryogénie callus induction: The white globular callus was divided and incubated on half strength MS medium supplemented with BA at 1.0 mg l-1 and 2,4-D at 5.0 mg l-1 for 4 weeks. At the end of this period, the embryogenic callus was obtained (Fig. 1c). Induction of somatic embryos: The embryogenic callus obtained from the previous step was incubated on half strength MS medium, supplemented with BA at 1.0 mg l-1 for the induction of somatic embryos. Somatic embryos were obtained after 4 weeks of culture (Fig. 1d, e). Embryo maturation: Somatic embryos were cultured on half strength MS medium, supplemented with BA at 1.0 mg l-1 and 2,4-D at 5.0 mg l-1 for embryo maturation. This step took about four weeks. Plantlet regeneration: The fully developed somatic embryos (Fig. 1e) were cultured, each in a test tube containing half strength MS medium, free of plant growth regulators. Fully developed plantlets were obtained (Fig. 1f). Plantlet acclimatization: The process of acclimatization was carried out on plantlets having good shoot and root system. The plantlets were removed from the culture vessels and washed with sterilized water to clean the root system from the remains of the growth medium. The plantlets were then placed in glass tubes containing half strength MS medium, ensuring the submergence of the root system. The glass tubes were then closed with aluminum foil and placed in a growth chamber for 24 hrs. Then, the plantlets were planted in an autoclaved soil mix containing sand and peat moss (2 : 1). The plantlets were then covered with glass cover for 3 - 4 weeks (Fig. 1g) and then glass covers were removed gradually. The process of acclimatization continued for 8 months, and the rate of survival was 100 % (Fig. 1h). Figure 1.: The time line of somatic embryogenesis and plantlet regeneration in citrus sinensis .cv. Local orange; a, isolated nucelus tissue; b, primary callus; c, embryogenic callus; d, e, germinating embryos; f, plantlet; g, plantlet during acclimatization; h, plant in pot after acclimatization. 3 RESULTS AND DISCUSSION It is evident from Fig. 1, that local orange (Citrus sinensis (L.) Osbeck) can be clonally mass propagated in vitro using somatic embryogenesis from nucellus derived callus. In the present work, successful embryogenic calli were developed from all culture media. Similar results were obtained by Pasqual and Ando (1988) with sweet orange cv. Vallencia. However, Miah et al. (2002), working with nucellus tissues of Citrus macroptera, found that embryogenic callus was obtained only from MS medium supplemented with malt extract. However, such differences in the response of Citrus species to culture media are probably genetically determined. It is obvious from the present work, that half strength MS media supplemented with BA at 1.0 mg l-1 induced the formation of somatic embryos (Fig. 1d, e). The importance of the benzyl adenine for the induction of somatic embryo has also been reported by Praveen et al. (2003) for Kinnow mandarin. Embryo germination and maturation occurred on half strength MS medium supplemented with BA at 1.0 mg l-1 and 2,4-D at 5.0 mg l-1. Similar results were obtained by Miah et al. (2002) for Citrus macroptera and Bhargara et al. (2003) for date palm, who showed the importance of benzyl adenine and auxins, for embryo germination and maturation. After embryo germination and maturation, they were transferred to half strength MS medium free of plant growth regulators and complete plantlets were obtained within 12 weeks (Fig. 1f) from the start of culturing the nucellus tissues, and to the time point when they were ready for acclimatization. The plantlets thus obtained through somatic embryogenesis were transferred to a soil mixture (sand : peat moss, 2 : 1) and the rate of survival was 100%. In conclusion, the results obtained in the present work demonstrate efficient cloning of local orange (Citrus sinensis (L.) Osbeck), through somatic embryogenesis. Furthermore, this in vitro culture method is useful not only for plant breeding and genetic studies, but also for studying the tolerance of orange trees to abiotic stresses, in particular, soil salinity, which is generally detrimental to plant growth and productivity in Iraq and worldwide. 3 REFERENCES Bhargara, S.C., Saxerna, S.N. and Sharma, R. (2003). In vitro multiplication of Phoenix dactylifera (L.). J. Plant Biochemistry and Biotechnology, 12: 43-47. Chen, R.Z., Li, G.G., Zhang, L.Y. and Li, K.L. (1990). A preliminary study of the factors affecting embryogenesis and plantlets regeneration from nucellus tissues of Citrus reticulata cv. Ponkan. Acta-Botanica Austrosinica, 6: 75-80. Juarez, J. and Navaro, L. (1977). Tissue culture techniques used in Spain to recover virus free citrus plants. Acta Horti, 78: 219-224. Miah, M.N., Islam, S. and Hadinzzaman, S. (2002). Regeneration of plantlets through somatic embryogenesis from nucellus tissues of Citrus macroptera Mont. var. anammensis (SatKara). Plant Tissue Culture, 12: 167-172. Murashige,T. and Skoog, F. (1962). A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant., 15: 473-497. Pasqual, M. and Ando, M. (1988). In: propagation of tropical and sub-tropical crops. (Bose, T.K., Mitra, K.S., Sadhu, M.K. and Das, P., eds.), Naya Prakash, Calcuta, India, 212 p. Praveen,S., Panwar, V., and Ahlawat, S. (2003). Somatic embryogenesis and plant regeneration in Kinnow Mandarin. J. Plant Biochemistry and biotechnology, 12: 163-165. Rangan, T.S., Murashige, T. and Bittevs, W.P. (1968). In vitro initiation of nucellar embryos in mono embryonic citrus. Hortscience, 3: 226-227. COBISS Code 1.01 Agrovoc descriptors: lycopersicon esculentum, tomatoes, varieties, fruit vegetables, plant production, cultivation, data collection, surveys, farm surveys, farmers, rural population, land ownership, ownership, development indicators, postharvest losses, crop management Agris category code: f01, e20, e51 Assessment of production practices of small scale farm holders of tomato in Bagrote Valley, CKNP region of Gilgit-Baltistan, Pakistan Muhammad SAEED AWAN1, Azhar HUSSAIN2, Tanveer ABBAS2 and Rehmat KARIM2 Received January 27, 2012; accepted February 23, 2012. Delo je prispelo 27. januarja 2012, sprejeto 23. februarja 2012. ABSTRACT The primary data used for the investigation were obtained through a questionnaire. One hundred and twenty (120) farmers were randomly selected; their education level, area of cultivation, time of planting, intercropping, varieties grown, fertilizer used, time of picking, packing, transportation and processing were looked at. It was found that out of 120 respondents, 52% were literate, and 48% were illiterate. 90% land holders were owners while remaining were tenants. Roma variety (46%) was preferred variety followed by Rio-Grind (38%) and Heirloom variety (16%). In terms of picking time, majority of farmers picked tomatoes in the afternoon (38%) or evenings (34%) and rest picked them in the mornings (28%). All the farmers transported tomatoes to local market either in wooden boxes (76%) or traditional baskets (24%). Majority of the farmers responded positively to drying tomato, but (27%) were unaware of processing procedures. Over all loss of tomato crop to fungal and viral diseases was estimated to be 24%. Key words: Tomato, production practices, post-harvest losses, assessment IZVLEČEK OCENJEVANJE PRIDELOVANJA PARADIŽNIKA NA MAJHNIH KMETIJAH V DOLINI BAGROTE, CKNP OBMOČJE GILGIT-BALTISTANA, PAKISTAN Podatki za raziskavo so bili pridobljeni z anketnim vprašalnikom. Naključno je bilo izbrano 120 kmetov glede na njihovo izobrazbo, velikost obdelovalne površine, čas sajenja, uporabo medposevkov, sorte paradižnika, uporabo gnojil, čas pobiranja, način pakiranja, transporta na trg in predelave. Raziskava je pokazala, da je bilo 52 % pridelovalcev pismenih in 48 % nepismenih. 90 % pridelovalcev so bili lastniki zemljišč, ostali so bili najemniki. Najbolj priljubljena sorta je bila 'Roma' (46%), sledili sta ji sorti 'Rio-Grind' (38 %) in 'Heirloom' (16%). Kmetje so najbolj pogosto pobirali paradižnike ob popoldnevih (38%) ali zvečer (34%), ostali zjutraj (28%). Večina kmetov je transportirala paradižnik na lokalne trge v lesenih zabojih (76%) ali v tradicionalnih košarah (24%). Večina pridelovalcev se je odzvala pozitivno na možnost sušenja paradižnikov, le manjši del (27%) ni poznal tega postopka predelave. Celokupna izguba pridelka zaradi glivnih in virusnih okužb je bila ocenjena na 24%. Ključne besede: paradižnik, tehnologija pridelave, izguba pridelka po obiranju, ovrednotenje 1 Prof. Dr., Department of Agriculture and Food Technology, Karakoram International University, Gilgit-Baltistan-Pakistan, seed.awan@kiu.ed.pk 2 Department of Agriculture and Food Technology, Karakoram International University, Gilgit-Baltistan-Pakistan 1 INTRODUCTION Tomato (Lycopersicum esculentum) is a staple fruit vegetable. Fresh fruits and vegetables are very important source of vitamins and minerals which are essential for human health. Tomato is one of the most important vegetables in the world. It is considered as an important cash and industrial crop in many parts of the world (Babalola et al., 2010). Tomatoes are grown as fresh market and as processing tomatoes. They are important for food industry as they serve as raw material for production of value added products (Soe, 2003). The domestic consumption and demand for tomato is growing due to increase in population. It is very important vegetable with substantial nutritional value. Moreover it is available at low price as compared to other vegetables. It is consumed in every home in different modes, such as vegetable, salad, ketchup, chatni and it is part of every delicious cuseine. Due to wide seasonal variations in Pakistan tomato is available throughout the year. Pakistan produces two crops annually first in spring and second in autumn. However, in southern Pakistan tomato can be grown throughout the year. Pakistan produced 560,700 tones tomatoes in 2008-9. Production/hectare was 10.50 tones. During 2008-09 total area under cultivation were 53, 400 hectares (Agric Stat, 2008-09). While Gilgit-Baltistan produced 6,455 metric tons tomatoes. Of which 3194 MT were consumed, 2293 MT were marketed, and 968 M.T were wasted. While, in Gilgit-Baltistan tomatoes were cultivated on 805 hectare (Agric Stat, 2009). Despite the remarkable progress made in increasing world food production at the global level, approximately half of the population in the third world does not have access to adequate food supplies. There are many reasons for this. For instance food losses to pests, diseases, lack of awareness of modern production practices, seed selection and post harvest problems. Evidence suggests that these losses tend to be highest in countries where the need for food is greatest (FAO, 1989; Oyewole and Oloko, 2006; Babalola et al., 2008). Optimum production of tomato requires intensive management practices that conserve and manage soil nutrients needed for maintaining soil fertility and water quality and for sustaining tomato production (Yafa et al., 2000). It is also common knowledge that production of tomatoes is declining due to some bacterial, fungal diseases and pest attacks. Furthermore, lack of resistant varieties and poor marketing add to farmer's woes. Therefore, this crop needs special attention of extension workers, researchers, policy makers and growers to identify the constraints, improve production methods and suggest remedial measures to enhance tomato production in Pakistan. This study was conducted to achieve following objectives. To review the production practices followed by the tomato producers in Bagrote valley. To propose new and innovative methods of replacing existing traditional production practices. 2 MATERIALS AND METHODS 2.1 Study area Bagrote valley is situated in the North-West of Gilgit at two hours drive from the city. The valley has fertile lands and is famous for the production of seasonal crops, like wheat, potato, maize and vegetables. Bagrote valley consists of eight villages. Irrigation system of valley consists of water cannels. This valley is famous for tomato production but in last few years production has steadily declined, so current study was conducted to assess production practices of small scale Stomato growers. 2.2 Data collection This study was based on primary data collected from tomato producers during Kharif 2010-11. Sample survey was carried out and personal interviews were held to collect the information. Before launching, the survey questionnaire was pre tested and was improved accordingly. Key informant technique was also followed to get authenticated information. 2.3 Sample size The survey included 120 randomly selected tomato growers. There are many estimation techniques. Frequency tables are very useful in knowing the trend related to a particular variable. The same technique was followed in analyzing results of this study. Percentage method was used to analyze farmers' responses related to production practices and post-harvest losses. The analysis was carried out in relation to percentage analysis on tomato; including education level, cultivation time, fertilizer use, intercropping, picking time, varieties grown, mode of transportation, processing, sale point and disease prevalence. 3 RESULTS AND DISCUSSION 3.1 Education level of farmers and their tenant status Literacy is one of the important characteristics of farmers that greatly influences the adoption of new technology. Data with respect to the literacy rate of sampled farmers were collected on the basis of their schooling years. Those who had completed school education were categorized as literate and those who had no formal school education were deemed as illiterate. It was observed that out of 120 farmers, 52% were literate while remaining 48% growers were illiterate. Tenancy is an agreement between land owners and farmers under which land owners lease out their land to tenants who work the land and pay agreed rent or hand over agreed share of crop to land owners (Amanullah, 1999). From our studies it was observed that 90% tomato growers were owners. Whereas, remaining 10% were tenants (Table 1). Table1: Number of farmers classified by their education level and tenure status Education Level Frequency Percentage Literate 62 52 Illiterate 58 48 Total 120 100 Tenure Status Owner Tenants 90% 10% 3.2 Time of cultivation & operational area held by the farmers Majority of the farmers planted tomatoes in August. However, some planted them in march as well (Table 2).Operational holding of farmers plays a significant role in the adoption of new technology. A number of researchers reported that there is an inverse relationship between farm size and productivity (Maureithi Table 2: Numbers of farmers classified by time of cultiv; et al, 1991 and Kapronczai and Tomka, 1991). While, other studies do not support this contention that farm size affects the productivity and inputs (Thakur et al., 1990). Data regarding operational land holdings showed that 71% of farmers had tomato patches measuring from 1-10 Marlas (one marla = 50 sq. yards),14% farmers had fields up to 10-20 Marlas and 15% had fields upto 20-30 Marlas. Time of Cultivation Frequency Percentage March 20 17 August 100 83 Total 120 100 3.3 Intercropping in tomato crop Our survey showed that majority of the farmers (54%) practiced intercropping in order to minimize the risks and maximize returns. 3.4 Tomato varieties grown by the farmers Our study showed that majority of the farmers used Roma variety (46%) followed by Rio-Grind (38%) and 28% farmers cultivated leafy vegetables, 12% Beans, 13% Cabbage, 3% Radish and 4% Corundum crops, while the remaining 46% did not practice intercropping in their fields. Heirloom (16%). Farmers prefer Roma and Rio-Grind tomato varieties because of their good shape, flesh and weight. These tomatoes are easy to market and farmers can get better returns. Heirloom variety was grown for home consumption and processing (Fig. 1). Figure 1: Percentage of different varieties grown in Bagrote valley 16% ^^^^ 46% 38% ■ Rio-Grind I 3.5 Tomato varieties Balanced use of fertilizers in proper quantities and their timely application is inevitable in getting a good yield. Research has shown that growing same crops on the same piece of land for years depletes soil nutrients and therefore, for raising good crop it becomes imperative to replenish the soil fertility with the application of organic and inorganic fertilizers. Commercial fertilizers are the major source of readily available nutrients to enhance crop production and achieve food security. The application of fertilizers in balanced ratio not only guarantees a good crop but also maintains Figure 2: Number of farmers 3.6 Picking time of tomatoes The time of picking is considered most important factor in post - harvest losses. Our study indicated that picking time is determined by the commitments of farmers with the transporters for short and long distance transportation. It was observed that the farmers, who transported their produce to the the natural fertility of the soil. Gurmani et al., 2003 reported that proper supply of nitrogen to crop is associated with the enhancement of photosynthetic activity, vigorous growth and dark green colour of plant leaves. Being a vital part of the building blocks of genes and chromosomes, phosphorus controls all the living processes in plants. It is not only essential for cell division but also for energy transport system in all cells (Saleem, 2003). It was observed in the present study that out of 120 farmers 38% farmers used manure (cow dung) Nitrophas, and Nitrate, 31% used manure & Nitrophas. While 31% used manure & Nitrate (Fig. 2) only. local and nearby markets, generally pick tomato early in the morning (28%). But most farmers, pick tomato in morning for drying as well. While the farmers who transport their produce to distant markets, pick their tomato in afternoon (38%) and evening time (34%) in order to make the produce ready for transportation and available for sale in the wholesale markets. Time of Picking Frequency Percentage Morning 33 28 Afternoon 46 38 Evening 41 34 Total 120 100 Table 3: Numbers of farmers classified by time of tomato picking 3.7 Packaging material used for tomato crop Packing of mechanically injured or fungus infested fruit increases probability of considerable deterioration (De Lucia and Assennato, 1994). Efforts were also made to develop a relationship between fungal infection and distance from the market. Remove bruised and damaged fruits and pack fruits with similar maturity stage in one container. Separate ripe fruits since these produced ethylene that could hasten the ripening process of unripe fruits. There are different modes of packaging. Generally, container-packing is considered ideal for packing fruits or vegetables because these are easy to handle, provide good protection from mechanical damage, have adequate ventilation and convenient for merchandising. For local markets tomatoes can be packed in wooden boxes or other traditional crates assuring careful handling. From the present study it was observed that for local markets cardboard boxes or wooden crates (76%) 70 to 80 kg and Traditional baskets (24%) with 30-35 kg capacity were used (Table 4). Table 4: Numbers of farmers classified by use of packaging material of tomato Material Used Frequency Percentage Wooden boxes 91 76 Traditional Baskets 29 24 Total 120 100 3.8 Sale points It was found that aU the tomato growers none of the growers transported their produce brought produce to local market for sale and to distant markets. Table 5: Numbers of farmers classified by sale points for tomato produce Sale Points Frequency Percentage Local Market 120 100 Outside 0 0 Total 120 100 3.9 Mode of transportation Most tomato growers (86%) transported their product to markets by jeeps while the remaining (14%) farmers used other sources to transport their produce. During transportation fruit passes through ripening, which is a complex phenomenon. It involves maturation, color change, production of ethylene, tissue softening, and change in respiration rate, fruit membrane thickness and permeability. During transportation the produce should be immobilized by proper packaging and stacking, to avoid excessive movement or vibration. Vibration and impact during transportation (Table 6) may cause severe bruising or other types of mechanical injury to the food (Gregor, 1987). Assessment of production... CKNP region of Gilgit-Baltistan, Pakistan Table 6: Numbers of farmers classified by mode of tomato transportation Mode of Transportation Frequency Percentage Jeeps 103 86 Others 17 14 Total 120 100 3.10 Knowledge of tomato processing Large quantities of tomato fruits are harvested each season, but post - harvest processing and preservation techniques are ineffective. Therefore, fruits spoil very early because of lack of appropriate system of preservation and processing (Francois, 1995). To reduce the post-harvest losses and over supply to the markets, it is essential that the surplus and over ripe produce be separated and processed. In order to know the farmers' knowledge of processing, tomato growers were asked whether they knew what can be produced from tomato crop. Of the total respondents, 27% responded negatively and the remaining 73%, responded positively (Table 7). They were using drying techniques and hence were aware of processing. Table 7: Numbers of farmers classified by tomato processing techniques What can be produced Frequency Percentage Drying 88 73 Others 0 0 Nothing 32 27 Total 120 100 3.11 Post - harvest losses in tomato crop The post harvest loss of tomato crop in Bagrote valley is 24% and the remaining is available with the growers for consumption and marketing. (Raja and Khokhar, 1993) stated that postharvest losses in fruits and vegetables range from 25-40% or even greater (Iqbal, 1996). The post harvest losses of tomato crop in Peshawar valley was 20% (Manzoor et al, 2006). Seasonal post harvest losses of fruits and vegetables are high in the tropics due to hot environmental conditions and moisture levels (MAEP, 1999). The deterioration of fruits and vegetables starts right after their harvest, if not properly harvested. Generally accepted methods for evaluating post - harvest losses of fresh produce do not exist. In the appraisal of an existing marketing operation, the accurate evaluation of losses is a problem. It may be conjectured that losses are huge, but there may be no figures to support this view (FAO, 2002). 3.12 Storage During the survey it was observed that most of the farmers picked their crop in afternoon and transported their produce to local markets in wooden Crates using jeeps as a mode of transportation. The estimated post harvest losses of tomato crop in Bagrote valley were 24% of the total production. These losses may occur during picking, handling transportation, etc. Due to poor storage conditions resistance of fruit and vegetables to natural disease usually declines, leading to infection by pathogens (Tefera et al, 2007). Many horticultural crops have a relatively short harvesting season. Storage is needed to extend the marketing period. Air-cooled common storage houses are often used in this regard. To delay ripening in tomato temperature should be greater than 2627 °C as they are harvested at different stages and stored. Although fully ripened tomatoes may be held at 2-5 °C before consumption for short time (Maul et al., 2000) but the mature green tomatoes should not be placed at temperature below 12 °C as it causes chilling injury which adversely affects quality and ripening (Saltveit, 2001). There is significant loss of weight and firmness in tomatoes during storage due to the effect of temperatures (Van Dijk et al., 2006) and there is relationship between the harvest and firmness changes in tomato. Different techniques are employed to improve the shelf life of fresh commodities. One of the techniques to improve shelf life of tomatoes is edible coatings (Baldwin et al, Table 8: Field diseases of tomato crop 1995). These edible coating can be used to preserve vegetables by providing barrier to moisture, oxygen and carbon dioxide and also improve its handling properties and contribute to the production of volatile aroma (Oliva et al., 2005). Absence of proper storage and marketing facilities, farmer is forced to sell their products at throw away prices. Sometimes farmers do not even get the two ways transportation costs back, so they would rather dump their produce near the market area than taking them back to home. 3.13 Tomato field diseases and insect damage During field visits three fungal, two bacterial and two insect pests causing damage were observed (Table 8). A study conducted in Sindh during 2004 revealed that various fungal, bacterial and viral diseases attack tomato crop. It was also reported that Rhizoctonia solani was isolated with highest frequency i.e. 60.0% (Rajput, 2004). Early blight Phytophthora infestans Fungal Late Blight Alternaría solani Fungal Gray leaf spot Stemphylium solani Fungal Fusarium wilt Fusarium oxysporium Fungal Bacterial spot Xanthomonas campestris Bacteria 4 CONCLUSION Based on the results and observations made during the survey, it seems that the current farming system of tomatoes, in Bagrote valley of CKNP region is inadequate. The farmers lack fundamental knowledge about production practices, disease and post harvest handling practices. Therefore the following recommendations are made: • Farmers must be provided extension lectures on new and innovative production methods. • Young and educated persons must be encouraged to take to farming and they must be provided financial incentives. • Farmers should be educated to adopt modern technologies for tomato production and they must be assured that it will work to their advantage. • Farmers must be helped with farm infra structures and provided with post-harvest farm facilities in order to avoid post-harvest losses. 5 REFERENCES Ammanullah, 1999. Constraints in wheat production (A case study of district Mardan). Unpublished M.Sc thesis. Deptt. of Agric. Econ. NWFP Agric. Univ., Peshawar. Agriculture statistics of Pakistan, 2008-09. Govt of Pakistan, Area, production of fruit,vegetables and Condiments. Ministry of Food and Agriculture (Economic wing) 2008-2000. p. 84. Agriculture statistics of Gilgit-Baltistan, 2009. Govt of Pakistan, Area, production of fruit, vegetables and cereals. Department of Agriculture Gilgit-Baltistan 2009. p.46. Babalola, D.A., Agbola, P.O. 2008. Impact of Malaria on Poverty Level: Evidence from Rural Farming Households in Ogun State, Nigeria. Babcock Journal of Economics & Finance 1 (1) 108 - 118. Babalola D. A., Makinde,Y.O., Omonona, B.T., Oyekanmi. M.O. 2010. Determinants of post harvest losses in tomato production: a case study of Imeko - Afon local government area of Ogun state. Journal of Life and Physical Science. Acta SATECH 3 (2): 14 - 18. Baldwin, E. A., M. O. Niesperos, P. E. Shaw and J. K. Burns, 1995. Effect of coating and prolonged storage condition on fresh orange flavour volatiles. De Lucia, M., Assennato, D. 1994. Agricultural engineering in development. Post-harvest operations and management of foodgrains. FAO Agricultural Service Bulletin No. 93. FAO, 1989. Prevention of losses fruit, vegetable and root crops: a training manual. United Nations Food and Agricultural Organization, Rome, Italy. Pp 1-3 Geinet, H., Woldetsadik, K. 2008. The effect of cultivar, maturity stage and storage environment on quality of tomatoes. J Food Eng., 87: 467-478. Iqbal, M. 1996.Type and extent of post harvest losses in horticultural commodities on Pakistan (pp: 33-42). In: Proceedings of National Conference on Post-harvest Technology of Horticulture Commodities, 10-12. Maul F., Sargent S.A., Sims E.A., Baldwin, M. 2000. Tomato flavor and aroma quality as affected by storage temperature. Journal of Food Sci., 65: 12281237. Oliva, G. I., Barbosa-canovas, G. V. 2005. Edible coatings for fresh-cut fruits. Crit. Rev. Food Sci. Nutri., 45: 657-67. Oyewole, B.O., Oloko, S.O. 2006. Agriculture and Food Losses in Nigeria-The Waout. Http://www.ivcs.org.uk/ijrs/April2006/Nigera. Rajput, M.I. 2004. Some Studies on the Control of Tomato Damping-off Caused Agent, M.Sc. (Hons) Thesis, SAUT, Tandojam. Saltveit, M.E. 2001. Chilling injury is reduced in cucumber and rice seedlings and in tomato pericarp discs by heat-shocks applied after chilling. Postharvest Biology and Tech., 21: 169-177. Soe, U.M. 2003. Value-Added Food Production Based on Farm Produce in Myanmar Ministry of Agriculture and Irrigation, Myanmar. Tefera, A.T. Seyoum,K., Woldetsadik. 2007. Effect of disinfection, packaging, and storage environment on the shelf life of mango. Biosyst. Engineer., 96: 1537-1550. Thakur D.R., Moorti, T.V., Sharma, H.R. 1990. Resource use farm size and returns to scale on tribal farm of Himachal Pardesh. Agric. Situation in India. 44:11,885-891. Deptt. of Agric. Econ. Himachal Pardesh, Krishi Vishva Vidyalaya, Palampur, India. Van Dijk C., Boeriu, F., Peter, T., Tijskens, L. M. M. 2006. The firmness of stored tomatoes (cv. Tradiro). 1. Kinetic and near infrared models to describe firmness and moisture loss. Journal of Food Eng., 77: 575-584. Yafa S., Sainju U. M., Sing. B.P. 2000. Fresh market tomato yield and soil nitrogen as affected by tillage, cover cropping and nitrogen fertilization. HortScience 35 (7), 1258-1262. COBISS Code 1.02 Agrovoc descriptors: dietary fibres ,human nutrition, chemicophysical properties, nutrition physiology, physiological functions, mankind, health, therapeutic diets, disease control Agris category code: s20, s30 Pomen prehranske vlaknine v prehrani človeka Terezija GOLOB1, Jasna BERTONCELJ2, Mojca KOROŠEC3 Received April 26, 2012; accepted July 05, 2012. Delo je prispelo 26. aprila 2012, sprejeto 5. julij 2012. IZVLEČEK Prispevek podaja definicijo in opredelitev prehranske vlaknine ter njeno vlogo v prehrani človeka. Predstavljena je delitev prehranske vlaknine glede na fizikalno-kemijske lastnosti in fiziološke učinke. Prikazani so fiziološki učinki topnih in netopnih komponent vlaknine, priporočila glede dnevno zaužite količine vlaknine in njena energijska vrednost. Prikazani so pozitivni učinki uživanja prehranske vlaknine na zdravje ljudi in na zaščito pred različnimi obolenji. Nakazani so dvomi o pretiranem pomenu prehranske vlaknine v prehrani. Ključne besede: prehranska vlaknina, fiziološki učinki prehranske vlaknine, zdravje, živila rastlinskega izvora ABSTRACT THE IMPORTANCE OF DIETARY FIBRE IN HUMAN NUTRITION The paper provides a definition of dietary fiber and describes its role in a human nutrition. Dietary fiber is presented in the respect of the physico-chemical properties and physiological effects. The recommendations for daily intake of fiber and the energy value of dietary fiber are stated. The positive effects of dietary fiber on human health and protection against various diseases are shown. The doubts about the exaggerated importance of dietary fiber in the diet are mentioned. Key words: dietary fibre, physiological effects of dietary fiber, health, plant-derived food 1 UVOD O prehrani človeka je veliko polemičnih razglabljanj, objavljenih različnih znanstvenih raziskav, pa tudi strokovnih prispevkov. Po navedbah Kendalla in sod. (2010) je meso v prehrano vključeno sicer že 2,6 milijona let, vendar naj bi naši davni predniki uživali v glavnem rastlinsko hrano, sestavljeno iz listne zelenjave, poganjkov, sadja, semen in oreščkov. Ta hrana je bila bogata s prehransko vlaknino in imela nizek glikemični nivo. Industrijska revolucija, ki ji je sledil hiter tehnološki napredek, je dramatično spremenila življenjski slog ljudi. V zadnjih 200 letih je hrana postala vse bolj predelana, kar ima za posledico občutno manjši vnos prehranske vlaknine. Različni načini vzreje živali, katerih glavni cilj je bil znižanje stroškov, so vplivali na občutno povečanje potrošnje hrane živalskega izvora, za katero pa je značilno, da ne vsebuje vlaknine in da je bogata z 1 Univerza v Ljubljani, Biotehniška fakulteta, Jamnikarjeva 101, SI-1000 Ljubljana; dr. živil. znan., izr. prof.; e-mail: terezija.golob@bf.uni-lj.si 2 prav tam kot 1; dr. živil. znan., doc.; e-mail: jasna.bertoncelj@bf.uni-lj.si 3 prav tam kot 1; univ. dipl. inž. živ. tehnol., asist.; e-mail: mojca.korosec@bf.uni-lj.si nasičenimi maščobami in s holesterolom. Prav ta drastična sprememba v naši prehrani naj bi bila vzrok, da je današnja populacija podvržena različnim kroničnim boleznim, kot so srčna obolenja in diabetes tipa 2 (Kendall in sod., 2010). Mnenja strokovnjakov o vlogi vlaknine v prehrani človeka so bila do nedavnega precej nasprotujoča. V preglednem članku Rodrigueza in sod., objavljenega v Trends in Food Science and Technology (2006), je podan kronološki pogled o vlogi prehranske vlaknine v prehrani. Navaja, da je Kellogg že 1923. govoril o pozitivnem delovanju vlaknine, medtem ko sta McCance in Lawrence leta 1929 opozarjala, da nerazgradljivi deli rastlin, ki sestavljajo prehransko vlaknino, dražijo (iritirajo) črevo. Nekoliko kasneje, leta 1947, naj bi Walker navajal, da večja vsebnost vlaknine pospešuje delovanje prebavil, Cleave pa je leta 1956 povezal nekatere bolezni s pomanjkanjem vlaknine, govoril je o sindromu pomanjkanja vlaknine ('deficiency of fibre syndrome'). Šele v 70-ih letih prejšnjega stoletja so številni znanstveniki poudarili pomen vlaknine in njeno vlogo pri zmanjšanju kardiovaskularnih bolezni, diabetesa in nekaterih oblik raka. Od tedaj so bile izpeljane številne raziskave, ki so poudarjale vlogo vlaknine pri preprečevanju in lajšanju kroničnih bolezni. Podpora vlogi vlaknine v preventivi in preprečevanju kroničnih bolezni še raste (Rodriguez in sod. 2006). O pomenu uživanja zadostne količine prehranske vlaknine v otroštvu in negativnih posledicah pri otrocih pri premajhnem vnosu vlaknine govori Williams (2006) v prispevku, objavljenem v The Journal of Pediatrics. Vzporedno pa zasledimo različne raziskave, v katerih poudarjajo, da je zaščitna vloga vlaknine pred pojavom različnih oblik raka predvsem posledica širokega spektra drugih, t.i. funkcionalnih komponent, ki jih vsebujejo živila, bogata z vlaknino in da slednji ne smemo pripisovati prevelikega pomena. 2 OPREDELITEV PREHRANSKE VLAKNINE Prehranske vlaknine ne predstavlja določena kemijska spojina, ampak jo sestavlja kombinacija kemijsko zelo različnih snovi, kot so: celuloza, hemiceluloza, pektin, lignin, gume in polisaharidi iz morskih alg ali bakterij. Celuloza, hemiceluloza in pektin so sestavni deli celičnih sten rastlin, zato jih imenujemo tudi strukturni polisahari. Med druge polisaharide, ki jih prav tako uvrščamo v prehransko vlaknino, čeprav niso sestavine celičnih sten, spadajo: gume (npr. gumi arabikum), rezervne gume (guar gume) in polisaharidi iz morskih alg (karagenan, agar, alginati); nekateri raziskovalci štejejo sem tudi rezistentni škrob (del škroba, ki ga encimi tankega črevesa ne razgradijo). Viri različnih komponent vlaknine so navedeni v preglednici 1. Pomen prehranske vlaknine v prehrani človeka Preglednica 1: Naravni viri različnih komponent prehranske vlaknine (Gray, 2006) Table 1: Natural sources of dietary fiber components (Gray, 2006) Komponenta vlaknine Glavni vir celuloza hemiceluloza lignin p-glukan pektin zelenjava, lesnate rastline, žitni otrobi žitna zrna žitni otrobi, luščine riža in stročnic, lesnate rastline zrna (ovsa, ječmena, rži, pšenice) sadje, zelenjava, stročnice, sladkorna pesa, krompir gume inulin in fruktooligosaharidi oligosaharidi rezistentni škrob stročnice, morske alge, mikroorganizmi (guar, karagenan, ksantan, guma arabika) cikorija, artičoka, čebula humano mleko, zrnate stročnice semena stročnic, žitna zrna, semena, surov krompir, zelene banane, staran kruh, koruzni kosmiči, ohlajen kuhan krompir, riž Glede na kompleksnost komponent, ki jih uvrščamo v vlaknino, se je tekom različnih obdobij spreminjala tudi definicija za vlaknino. Večina definicij označuje analitične kriterije (predvsem topnost v vodi), nič pa ne pove o viskoznosti in fermentabilnosti, torej o fizikalno-kemijskih lastnostih, ki lahko pomembno vplivajo na delovanje prebavnega trakta. Še danes številni strokovnjaki navajajo, da je natančna opredelitev prehranske vlaknine sporna. Medtem ko ena izmed fizioloških definicij pravi: »prehranska vlaknina so ostanki rastlinskih celičnih sten, ki so odporni na encimsko hidrolizo v tankem črevesu«, pa ena izmed kemijskih opredelitev definira: »prehranska vlaknina so neškrobni polisaharidi« (Theubadin in sod., 1997; Slavin, 2003). Najpogosteje uporabljena definicija je naslednja: »»prehranska vlaknina je kompleksna mešanica neprebavljivih polisaharidov (celuloze, hemiceluloz, oligosaharidov, pektina, gum), voskov in lignina, ki jih najdemo predvsem v rastlinskih celičnih stenah. To so snovi, ki jih človekovi prebavni encimi ne razgradijo do komponent, ki bi se absorbirale v zgornjem prebavnem traktu«. Tosh in Yada (2010) navajata, da je pomen uživanja prehranske vlaknine za zdravje v veliki meri posledica različnih fizioloških učinkov in je zato ta vidik vključen tudi v definicijo ameriškega združenja AACC (American Association for Clinical Chemistry), ki se glasi: »prehranska vlaknina so užitni deli rastlin ali ogljikovim hidratom podobne spojine, ki so odporne na prebavo in absorpcijo v človeškem tankem črevesu in se popolno ali delno fermentirajo v debelem črevesu. Prehranska vlaknina so polisaharidi, oligosaharidi, lignin, in druge rastlinske snovi. Prehranska vlaknina ima ugodne fiziološke učinke, pospešuje prebavo, in/ali vpliva na zniževanje nivoja holesterola in/ali glukoze v krvi«. V izogib različnim definicijam je v Pravilniku o spremembah Pravilnika o označevanju hranilne vrednosti živil (U.l. 87, 2009 z dne 02. 11. 2009) skladno z Direktivo Komisije 2008/100/ES (z dne 28. oktobra 2008) o spremembi Direktive Sveta 90/496/EGS podana naslednja opredelitev snovi, ki predstavljajo prehransko vlaknino: Prehranska vlaknina so polimeri ogljikovih hidratov s tremi ali več monomerskimi enotami, ki se ne prebavijo niti absorbirajo v tankem črevesu človeka in spadajo v naslednje kategorije: - užitni polimeri ogljikovih hidratov, naravno prisotni v živilih v obliki, v kateri se zaužijejo, - užitni polimeri ogljikovih hidratov, ki so bili pridobljeni iz surovine za živilo s fizikalnimi, encimskimi ali kemijskimi sredstvi in, ki imajo ugoden fiziološki učinek, dokazan s splošno sprejetim znanstvenim dokazom, - užitni sintetični polimeri ogljikovih hidratov, ki imajo ugoden fiziološki učinek, dokazan s splošno sprejetim znanstvenim dokazom. V istem pravilniku je navedena tudi energijska vrednost prehranske vlaknine, ki znaša 8 kJ/g oziroma 2 kcal/g. Torej moramo pri vrednotenju hranilne vrednosti živila, bogatega z vlaknino, poznati njeno vsebnost in izračunati njeno energijsko vrednost. Do nedavnega smo prehransko vlaknino pri nepoznavanju njene vsebnosti upoštevali kot del ogljikovih hidratov, pri poznavanju njene vsebnosti, pa smo le-to odšteli od skupne vsebnosti ogljikovih hidratov in nato le za izkoristljive ogljikove hidrate izračunali energijsko vrednost. 2.1 Kje najdemo prehransko vlaknino Vlaknino najdemo le v živilih rastlinskega izvora. Glede na obliko, v kateri ljudje uživamo prehransko vlaknino, govorimo o: - živilih rastlinskega izvora: sadje, zelenjava, oreščki, žita in njihovi izdelki; komponente vlaknine se nahajajo predvsem v celičnih stenah zunanjih delov plodu ali zrna (v perikarpu, alevronski plasti), precej manj v celičnih stenah endosperma, - izdelkih z dodano vlaknino (npr. kruh, v katerem je del pšenične moke nadomeščen z otrobi, z ječmenovo ali ovseno moko); - nadomestkih hrane (prehranskih dopolnilih); tu mislimo na vlaknino v obliki kapsul ali tablet. 3 DELITEV PREHRANSKE VLAKNINE Vlaknino delimo glede na njene fizikalno-kemijske lastnosti in fiziološko vlogo na (Gray, 2006): - topno in netopno vlaknino, - naravno prehransko vlaknino in funkcionalno vlaknino, - viskozno in neviskozno vlaknino, - fermentirajočo in nefermentirajočo vlaknino. 3.1 Topna in netopna prehranska vlaknina Večina znanstvenikov se strinja glede delitve vlaknine na topno in netopno v vodi. Ta podatek je pomemben tako za analizo vsebnosti vlaknine kot za razumevanje različnih funkcij, ki jih imajo posamezne komponente vlaknine v telesu. Med topno vlaknino uvrščamo gume, psilium, pektin, P-glukane in nekatere hemiceluloze, med netopno pa lignin, celulozo, hemicelulozo in nekatere pektine. Topno vlaknino najdemo v vseh živilih rastlinskega izvora, vendar v zelo različnih količinah (preglednica 2). Živila, bogata s topno vlaknino so: ovseni kosmiči, ječmen, stročnice (grah, soja, bob), nekatere vrste sadja in sadni sokovi (slive, jagode, banane, jabolka, agrumi, marelice, datlji, rozine, slivov sok), nekatere vrste zelenjave (brokoli, korenje, pesa, sladek krompir, čebula) in laneno seme. Glavna značilnost topne vlaknine je njena topnost v vodi in s tem povezane različne pozitivne fiziološke funkcije. Tudi netopno vlaknino najdemo v različnih deležih zastopano v širokem spektru živil rastlinskega izvora. Bogat vir netopne vlaknine so zlasti: pšenični in koruzni otrobi, polnozrnata živila, oreščki in semena, zelenjava (stročji fižol, cvetača, bučke, 3.2 Naravna prehranska vlaknina in funkcionalna vlaknina S pojmom naravna prehranska vlaknina označujemo komponente, ki se nahajajo v naravnih prehranskih virih. Sem štejemo: celulozo, lignin, hemicelulozo, pektin, gume, P-glukane, inulin in oligofruktozo ter neprebavljivi škrob. Kot funkcionalno vlaknino pa opredeljujemo izolirano naravno ali sintetično vlaknino, ki jo lahko dodajamo živilom in ima v telesu dokazan pozitiven fiziološki učinek. Med funkcionalno vlaknino spadajo poleg vseh zgoraj naštetih izoliranih komponent vlaknine tudi hitin (nahaja se v skeletu hrustančnic, npr. rakov), psilium (nahaja se v lupinicah trpotčevih semen) ter fruktooligosaharidi, polidekstroza, polioli in neprebavljivi zelena), nekatere vrste sadja (avokado in banane) in olupki nekaterih vrst sadja, krompirja, paradižnika, čebule. Komponente netopne vlaknine so v vodi netopne in imajo pomembno vlogo pri prehodu hrane skozi prebavni trakt. 2,02 3,27 1,82 2,07 1,70 3,63 2,47 3,00 2,73 1,22 2,53 2,95 2,14 1,89 1,81 0,00 4,00 6,14 8,22 dekstrini, ki jih uporabljamo kot aditive v proizvodnji živil. Na International Life Science Institute-ILSI Europe (1999) so definirali, da lahko »živilo štejemo za funkcionalno, če je bilo dokazano, da ima poleg hranilnega učinka blagodejen vpliv na eno ali več fizioloških funkcij, pri čemer je ta pomembna za izboljšanje zdravja ljudi in/ali zmanjšanje tveganja za pojav nekaterih bolezni«. Z rezultati številnih raziskav so potrdili različne učinke prehranske vlaknine, na osnovi katerih jo lahko obravnavamo kot funkcionalno sestavino hrane (Elleuch in sod. 2011; Tosh in Yada, 2010; Cui in sod., 2011; Slavin, 2005). Poleg tega so v različnih raziskavah proučevali dodajanje vlaknine kot funkcionalnega dodatka: npr. Elleuch je s sod. (2008) proučeval dodajanje ekstraktov datljev; Tosh Preglednica 2: Vsebnost prehranske vlaknine v nekaterih živilih rastlinskega izvora (Souci in sod., 2008) Table 2: Dietary fiber content in some plant-derived foods (Souci et al., 2008) Živilo Vsebnost prehranske vlaknine (g/100 g) topna prehranska vlaknina netopna prehranska vlaknina skupna prehranska vlaknina jabolko 0,48 1,54 hruška 0,61 2,66 banana 0,62 1,20 krompir 0,92 1,15 krompir, kuhan z lupino 0,74 0,96 korenje 1,74 1,89 korenje, kuhano 1,17 1,30 brokoli 1,30 1,70 brokoli, kuhan 0,50 2,23 endivija 0,18 1,04 rdeča pesa 0,48 2,05 belo zelje 1,33 1,62 kislo zelje, odcejeno 0,84 1,30 stročji fižol 0,88 1,01 čebula 0,29 1,52 ovseni kosmiči 4,95 5,08 koruzni kosmiči 1,20 2,80 oreh 0,84 5,30 lešnik 0,42 7,80 1 in Yada (2010) sta proučevala vpliv dodatka moke iz stročnic (fižola, čičerike, leče in graha); Galanakis (2011) in Anil (2007) navajata možnost uporabe vlaknine iz stranskih produktov pri predelavi oljk (ostanek po stiskanju olja) oziroma pri praženju lešnikov (ovojnica); Peerajit in sod. (2012) so proučevali funkcionalne lastnosti ekstrakta vlaknine iz lupine limet. Pri obogatitvi izdelkov z vlaknino velja opozoriti na zahtevno nalogo živilskih tehnologov zaradi velike različnosti v kemijski strukturi in različnih funkcionalnih lastnosti posameznih komponent vlaknine (Cui in sod., 2011). 3.3 Viskozna in neviskozna prehranska vlaknina Nekatere komponente vlaknine tvorijo v kombinaciji z vodo viskozne raztopine, ki vplivajo na počasnejšo absorpcijo nekaterih hranil, na počasnejše praznjenje želodca, na nižji nivo krvnega holesterola in na uravnavanje nivoja glukoze v krvi (Jenkins in sod., 2004). Med viskozno vlaknino spadajo nekatere gume, psilium, pektin in P-glukani. Kristensen in Jensen (2011) sta v reviji Appetite objavila članek o pomenu viskoznosti vlaknine pri uravnavanju apetita in na občutek sitosti. Poudarjata, da lakoto in vnos hrane regulirajo sicer različni fiziološki vplivi, med katerimi pa je viskoznost prehranske vlaknine eden pomembnejših. 3.4 Fermentirajoča in nefermentirajoča prehranska vlaknina Nekatere komponente vlaknine v črevesju s pomočjo bakterij fermentirajo, pri čemer nastajajo plini in kratkoverižne maščobne kisline, ki se lahko absorbirajo in so tako vir energije. Med visoko fermentirajočo vlaknino spadajo: inulin, oligofruktoza, pektin, P-glukani in nekatere gume. Medtem ko spadata hemiceluloza in rezistentni škrob med delno ali slabo fermentirajočo, pa se lignin in celuloza smatrata za nefermentirajoči komponenti. Živila z veliko vsebnostjo fermentirajoče vlaknine so ječmen, oves, sadje in zelenjava, nefermentirajočo vlaknino pa vsebujejo žita in otrobi oz. živila z veliko vsebnostjo celuloze (Rodriguez in sod., 2006). 4 PRIPOROČILA GLEDE VNOSA PREHRANSKE VLAKNINE Referenčne vrednosti za vnos hranil (2004) navajajo orientacijsko vrednost za vnos prehranske vlaknine pri odraslih najmanj 30 g na dan, to je približno 3 g/MJ oziroma 12,5 g/1000 kcal pri ženskah in 2,4 g/MJ oziroma 10 g/1000 kcal pri moških. Po priporočilih prehranskih strokovnjakov je dnevno zaužita količina vlaknine med 20 in 40 g. Glede na sodobni način prehranjevanja večina ljudi uživa hrano, pripravljeno iz predelanih in prečiščenih sestavin, z veliko mesa in sladkarij, zato tega odmerka ni tako lahko doseči. Strokovnjaki opozarjajo, da je vnos vlaknine s prehrano v zahodnih deželah pod priporočili, manjši kot ga potrebujemo za zdravo življenje (Baixauli in sod., 2008). Če želimo povečati vnos vlaknine v telo, je to potrebno storiti postopoma, in sicer za največ 5 g v 14-ih dneh. Priporočajo, da bi uživali pestro hrano (sadje, zelenjavo, žita ter stročnice), ker bi s tem zagotovili organizmu tako po sestavi kot po učinkovanju različne komponente prehranske vlaknine. 5 VPLIV PREHRANSKE VLAKNINE NA ZDRAVJE LJUDI IN BOLEZNI Na osnovi rezultatov številnih znanstvenih prehranska vlaknina pomembno vlogo pri raziskav je sprejeto prepričanje, da ima preprečevanju številnih bolezni, in da prehrana z veliko vsebnostjo vlaknine, oziroma, da hrana, ki je bogata z žiti, s sadjem in z zelenjavo, pozitivno vpliva na zdravje. Večje uživanje vlaknine povezujejo tudi z zmanjšano incidenco za več vrst raka (Peerajit in sod., 2012). Kljub temu, da je večina sestavin prehranske vlaknine neprebavljivih, ker jih encimi, prisotni v debelem črevesu, ne morejo razgraditi, so izpostavljene aktivnostim bakterijskih encimov, ki jih lahko delno razgradijo. Kot poudarjajo Rodriguez in sod. (2006), je obseg te razgradnje odvisen od vrste bakterijske flore. Dejavnika, ki so ju znanstveniki v povezavi z vlaknino proučevali, sta bila čas prehoda skozi debelo črevo in viskoznost. Čas prehoda skozi črevo vpliva na trajanje stika med bakterijskimi encimi in komponentami prehranske vlaknine, ki omejujejo obseg njihove razgradnje (30-90 % polisaharidov, večina hemiceluloze ter pektin). Ta razgradnja se začne z zunanjo celično hidrolizo, ki pretvarja polisaharide v mono- in disaharide, temu pa sledi anaerobna glikoliza, katere končni produkti so acetat, butirat in propionat. Glavni učinek v tankem črevesju je povezan z viskoznostjo polisaharidov, komponent topne vlaknine, kot so pektin in gume, ki zmanjšujejo asimilacijo hranljivih snovi, medtem ko netopne komponente tu ne igrajo pomembne vloge. Iz visoko fermentirajočih snovi (pektina), ostankov slabše fermentirajočih polimerov (celuloze in hemiceluloze) in vode, ki jo te komponente vežejo in zadržujejo, nastaja bakterijska masa, ki je odgovorna za povečanje mase blata (Rodriguez in sod., 2006). 5.1 Prehranska vlaknina in telesna teža V prispevku, objavljenem v reviji Nutrition, je Slavin (2005) prikazal pregled raziskav o vplivu prehranske vlaknine na telesno težo in mehanizme njenega delovanja. Podaja teoretične razloge, s katerimi prehranska vlaknina pomaga pri vzdrževanju telesne teže. Pravi, da deluje prehranska vlaknina kot fiziološka ovira vnosa energije z najmanj tremi mehanizmi: nadomesti hranila in izkoristljive kalorije v hrani; vpliva na povečano žvečenje, kar omeji vnos hrane in pospeši izločanje sline in prebavnih sokov; zmanjša absorpcijo hranil v tankem črevesju. Z vlaknino bogata hrana ima manjšo energijsko vrednost. Torej, če uživamo konstantno količino hrane, ki ima na račun večje vsebnosti vlaknine nižjo energijsko vrednost, vplivamo na zmanjšanje teže. Ker pa ima vlaknina zaradi sposobnosti povečanja volumna in viskoznosti vpliv na občutek sitosti in nasitno vrednost, smo z uživanjem enake količine hrane z nizko energijsko vrednostjo in veliko vsebnostjo vlaknine prej siti. Poleg tega je dokazano, da vlaknina lahko blokira ali omeji absorpcijo makrohranil in s tem pomaga pri kontroli telesne teže. Celo zelo majhne spremembe v absorpciji hranil imajo dolgoročno značilen vpliv na telesno težo. Tudi počasnejše praznjenje želodca je učinek, ki ga pripisujemo uživanju hrane bogate z vlaknino, predvsem z viskozno vlaknino. Upočasnjeno praznjenje želodca poveča občutek polnosti, upočasni absorpcijo glukoze in drugih hranil in tako vpliva na telesno težo. Lluch in sod. (2010) so ugotovili, da je poleg tega, da je še dve uri po obroku, ki je vseboval manj maščob in bil obogaten z beljakovinami in vlaknino zmanjšan tek, manjša tudi zaužita količina naslednjega obroka. 5.2 Prehranska vlaknina in čas prehajanja skozi črevesje Prehranska vlaknina velja za najpomembnejši dejavnik, ki vpliva na maso blata in hitrost peristaltike. Problem zaprtja obravnavamo običajno kot posledico uživanja nezadostne količine prehranske vlaknine. Thebaudin in sod. (1997) omenjajo, da je fiziološki učinek vlaknine v črevesju odvisen od deleža netopne oziroma topne vlaknine. Netopna vlaknina poveča maso blata in pogostost praznjenja, mehča blato in skrajšuje čas prehajanja skozi črevesje. Sposobnost vlaknine za zadrževanje vode je pomembna pri formiranju blata. Povečanje mase blata pripisujejo povečanju bakterijske mase, neprebavljenim vlakninskim ostankom in količini vode v blatu. Učinki vlaknine na maso blata so različni glede na vrsto in vir vlaknine, deloma pa vpliva tudi metoda priprave hrane. Vlaknini iz žit običajno pripisujejo večjo učinkovitost pri večanju teže blata kot vlaknini iz sadja. Topna vlaknina, kot je pektin, ne vpliva bistveno na funkcijo debelega črevesa ali skrajšanje časa prehoda; črevesna mikroflora jo popolnoma razgradi. 5.3. Prehranska vlaknina in rak Obstajajo rezultati številnih raziskav, v katerih so proučevali vpliv prehrane z veliko vsebnostjo vlaknine na zdravje in na pogostnost obolevanja za različnimi oblikami raka. Domnevno zaščitno vlogo pred rakom pri uživanju hrane bogate z vlaknino je močno podprl Burkitt (1973). Tudi Willett in sod. (1992) so v obsežni raziskavi v Veliki Britaniji preučevali učinke vnosa vlaknine skupaj z drugimi sestavinami hrane na pojavnost raka debelega črevesa pri ženskah. Ugotovili so, da je zmanjšano tveganje za pojav raka debelega črevesa povezano z večjim vnosom vlaknine s sadjem. Vzporedno pa lahko spremljamo rezultate raziskav, v katerih opozarjajo na težave pri oceni epidemioloških študij in o direktni povezavi med uživanjem hrane bogate z vlaknino in manjšo pojavnostjo raka debelega črevesa. Saj z uživanjem sadja, zelenjave, žit vnašamo v organizem tudi druge zaščitne snovi, kot so vitamin C, vitamin E in P-karoten. Rezultati 13-ih primerjalnih študij so pokazali, da je vsaka komponenta posamično (P-karoten, askorbinska kislina in vlaknina) pomembno povezana z zmanjšanim tveganjem za pojav raka in težko zaključimo, da je to posledica samo vnosa vlaknine (Thebaudin in sod., 1997). Nekateri raziskovalci so predlagali naslednji mehanizem, s katerim lahko prehranska vlaknina varuje pred rakom debelega črevesa: netopna vlaknina (npr. pšenični otrobi) poveča volumen blata in razredči njegovo vsebino, kar zmanjšuje interakcije med črevesno sluznico in vsemi rakotvornimi snovmi v blatu; krajši čas prehoda skozi črevesje zmanjša možnost interakcij mutagenov iz blata s črevesnim epitelom; vlaknina, kot fermentacijski substrat, spremeni tudi delovanje prebavne mikroflore, kar privede do spremembe ali zmanjšanja nastanka mutagenov; nekatere vrste vlaknine lahko celo adsorbirajo mutagene agense in s tem pospešijo njihovo izločanje (Thebaudin in sod., 1997). Možen mehanizem zaščitnega učinka vlaknine proti raku dojk je, da večji vnos vlaknine z večjim izločanjem blata vpliva na večje izločanje estrogenov, ki jih povezujejo s povečanim tveganjem za pojav raka dojk. Vendar opozarjajo, da so podatki o tem vplivu še nejasni. Tudi z raziskavo, v kateri so medicinske sestre uživale 22 g vlaknine na dan, niso dokazali varovalnega učinka vlaknine (Willet, 1992). V obsežnem pregledu izsledkov raziskav je bilo ugotovljeno, da iz dosedanjih literaturnih podatkov ne moremo zaključiti, da ima vlaknina zaščitni učinek niti pred rakom debelega črevesa niti rakom dojke, kljub temu, da so številne študije pokazale trende v tej smeri. Potrebne so še dodatne raziskave. 5.4 Vlaknina in presnova ogljikovih hidratov, beljakovin in maščob Ugotovljeno je, da lahko vlaknina vpliva na razpoložljivost ogljikovih hidratov v prebavnem traktu. Ta učinek je bil potrjen pri bolnikih s sladkorno boleznijo, pri katerih se je raven glukoze v krvi zmanjšala ob prehrani bogati z vlaknino. Theubaudin in sod. (1997) menijo, da netopna prehranska vlaknina nima vpliva na presnovo ogljikovih hidratov, medtem ko topna in viskozna vlaknina vplivata na zmanjšanje nivoja postprandialne glukoze v krvi. Glede vpliva vlaknine na presnovo beljakovin pa so številne študije pokazale, da je povečan vnos vlaknine v prehrani povezan s povečanim izločanjem dušika z blatom. Dušikove snovi so v veliki meri odvisne od bakterijskega izvora; povečanje mase blata pa kaže pri hrani bogati z vlaknino na povečano rast bakterij. Avtorji menijo, da imamo zaenkrat še premalo dokazov o tem, da bi prehranska vlaknina vplivala na presnovo in absorpcijo beljakovin. Poudarjajo nujnost nadaljnjih raziskav (Thebaudin in sod., 1997). Eggum (1992) ugotavlja, da je vpliv prehranske vlaknine na presnovo beljakovin v veliki meri odvisen od strukture in kemijske sestave vlaknine. Bistveno bolj pa so proučevani učinki vlaknine na presnovo lipidov. Ugotovljeno je bilo, da vlaknina vpliva na absorpcijo lipidov, saj močno zavira delovanje lipaz trebušne slinavke, ki sodelujejo pri presnovi lipidov. Po drugi strani pa prehranska vlaknina prispeva k zmanjšanju ravni holesterola in lipoproteinov nizke gostote v plazmi, kar je povezano z redčenjem in z večjim izločanjem žolčnih kislin (Rodríguez, 2006). V raziskavi o učinkih topne vlaknine na serumske lipide so ugotovili, da topna vlaknina vpliva na znižanje ravni lipoproteinskega holesterola nizke gostote LDH v serumu. Vezanje soli žolčnih kislin na komponente prehranske vlaknine spremeni presnovo holesterola, oziroma izločanje holesterola iz telesa. Z vezavo žolčnih kislin nastajajo žolčne soli, ki se s pomočjo blata odvajajo iz telesa. Tako je onemogočena resorpcija žolčnih kislin iz tankega črevesa nazaj v jetra, kjer se iz njih tvori holesterol LDL, povzročitelj arterioskleroze. Gallaher in sod. (1992) pripisujejo ta pozitiven učinek predvsem prehranski vlaknini iz ječmena in sladkorne pese. Pri proučevanju vpliva vlaknine na presnovo maščob je potrebno omeniti kratko verižne maščobne kisline (SCFA), ki nastajajo v debelem črevesu pri bakterijski razgradnji prehranske vlaknine. Številni raziskovalci menijo, da SCFA (zlasti propionat) zavirajo sintezo jetrnega holesterola (Roberts in sod., 1994). 5.5 Prehranska vlaknina in biološka izkoristljivost vitaminov in mineralov Vnos hrane, bogate z vlaknino, vpliva na delovanje encimov in podaljša čas prehoda hrane, kar naj bi vplivalo na povečano absorpcijo vitaminov. Vendar pa nekatera živila vsebujejo tako imenovane zaviralce izkoriščanja vitaminov (npr. inhibitorji proteaz), ki zmanjšujejo njihovo topnost/sproščanje. O učinkih prehranske vlaknine na biološko izkoristljivost vitaminov je bilo opravljenih le malo raziskav; največ pozornosti je bilo namenjene vitaminoma E in D. Ugotovili so, da so imele podgane, krmljene z grobimi pšeničnimi otrobi, nižji nivo tokoferola v jetrih kot podgane, krmljene s finimi gladkimi pšeničnimi otrobi ali celulozo. Nekatere študije so pokazale, da lahko velika vsebnost vlaknine v hrani vodi do večjega izločanja vitamina D. To razlagajo z nizkim statusom vitamina D pri vegetarijancih in pri makrobiotični dieti (Dagnelie, 1991). Biološka izkoristljivost mineralov je odvisna od količine zaužite hrane, od količine hrane, ki se v telesu absorbira in izkoristi. Domnevajo, da velik vnos vlaknine lahko zmanjša absorpcijo mineralov zaradi interakcij med minerali in vlaknino in je zato težko napovedati biološko izkoristljivost mineralov. Vpliv vlaknine na biološko izkoristljivost mineralov je odvisen predvsem od vrste vlaknine. Večina raziskav je vključevala pšenične otrobe. Najbolj raziskane so interakcije prehranske vlaknine z železom, s cinkom in s kalcijem. Številne študije so pokazale škodljiv vpliv vlaknine iz pšenice in koruze, pa tudi posameznih komponent vlaknine (guar gume, lignina in psilium sluzi) na absorpcijo železa in cinka. Medtem ko so rezultati drugih študij pokazali, da vlaknina ne zavira absorpcije železa in cinka. Te nasprotujoče ugotovitve so morda posledica tega, ker se vlaknina pogosto pojavi skupaj s fitatom, dokazanim zaviralcem absorpcije železa in cinka pri ljudeh in podganah. Dokazali so, da odstranitev fitata (kar je med predelavo izvedljivo) izboljšuje biološko izkoristljivost železa, cinka in kalcija. Tudi Thebaudin in sod., (1997) poudarjajo, da nikakor ne smemo slabše absorpcije mineralov pripisati le tvorbi kelatov med vlaknino in minerali, da na biološko izkoristljivost mineralov oziroma zmanjšano absorpcijo mineralov vpliva poleg vlaknine tudi fitat. 6 ZAKLJUČEK Čeprav je o lastnostih prehranske vlaknine veliko znanega, ostajajo še vedno številni nepojasnjeni vidiki, predvsem glede vpliva posameznih komponent vlaknine na nekatere patološke pojave. Ugotavljamo, da je danes jasno opredeljena le definicija vlaknine, dobro pa so dokumentirani tudi različni koristni učinki na zdravje ljudi, ki omogočajo, da vlaknino opredeljujemo kot funkcionalno sestavino, s širokim potencialom uporabe. Po pregledu različnih študij o prehranski vlaknini lahko povzamemo, da je na tem raziskovalnem področju še veliko vidikov, ki so potrebni nadaljnjih preiskav. Smatramo, da so za boljše poznavanje natančne strukture posameznih komponent prehranske vlaknine in razumevanje njihovih fizioloških učinkov na človeško telo potrebne kompleksne študije, v katerih bi sodelovali raziskovalci iz različnih področij znanosti: kemije, biokemije, biotehnologije, biologije, fiziologije, prehrane in medicine. Z rezultati take raziskave bi izgradili večjo in multidisciplinarno bazo, ki bo omogočala univerzalni dogovor o opredelitvi prehranske vlaknine, definirala metode za analizo njene vsebnosti ter natančno opredelila fiziološko vlogo posameznih komponent. 7 VIRI Anil, M. 2007. Using of hazelnut testa as a source of dietary fiber in breadmaking. Journal of Food Engineering, 80: 61-67. Baixauli, R., Salvador, A., Hough, G., Fiszman, S.M. 2008. How information about fibre (traditional and resistant starch) influences consumer acceptance of muffins. Food Quality and Preference, 19: 628-635. Burkitt, D.P. 1973. 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Dietary fibre and fibre-rich by-products of food processing: Characterisation, technological functionality and commercial applications: A review. Food Chemistry 124, 411-421. Elleuch, M., Besbes, S., Roiseux, O., Blecker, C., Deroanne, C., Drira, N.E., Attia, H. 2008. Date flesh: Chemical composition and characteristics of the dietary fibre. Food Chemistry, 111: 676-682. Galanakis, C.M. 2011. Olive fruit dietary fiber: components, recovery and applications. Trends in Food Science & Technology, 22: 175-184. Gallaher, D.D. Locket, P.L., Gallaher, C.M. 1992. Bile acid metabolism in rats fed two levels of corn oil and brands of oat, rye and barely and sugar beet fiber. Journal of Nutrition, 122: 473-481. Gray, J. 2006. Dietary fibre - definition, analysis, physiology and health. Brussels, International Life Sciences Institute, ILSI Europe: 36 str. Jenkins, D.J.A., Marchie, A., Augustin, L.S.A., Ros, E., Kendall, C.W.C. 2004. Viscous dietary fibre and metabolic effects. 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Ljubljana, Ministrstvo za zdravje Republike Slovenije: 29-53. Roberts, D.C., Truswell, A.S., Bencke, A., Dewar, H.M., Farmakalidis, E. 1994. The cholesterol lowering effect of a breakfast cereal containing psyllium fibre. Medical Journal of Australia, 161: 660-664. Rodríguez, R., Jiménez, A., Fernández-Bolaños, J., Guillén, R., Heredia, A. 2006. Dietary fibre from vegetable products as source of functional ingredients. Trends in Food Science & Technology, 17: 41-48. Slavin, J.L. 2003. Impact of the proposed definition of dietary fiber on nutrient databases. Journal of Food Composition and Analysis, 16 (3): 287-291. Slavin, J.L. 2005. Dietary fiber and body weight. Nutrition, 21: 411-418. Souci, S.W., Fachmann, W., Kraut, Ht.h 2008. Food Composition and Nutrition Tables. 7th ed. London, Taylor and Francis Group: 1364 str. Thebaudin, J.Y., Lefebvre, A.C., Harrington, M, Bourgeois, C.M. 1997. Dietary fibres: Nutritional and technological interest. Trends in Food Science & Technology, 8 (2): 41-48. Tosh, S.M., Yada, S. 2010. Dietary fibres in pulse seeds and fractions: Characterization, functional attributes, and applications. Food Research International, 43: 450-460. Willet, W.C. 1992. Dietary fat and fiber in relation to risk of breast cancer. Journal of the American Medical Association, 268: 2037-2044. Williams, C.L. 2006. Dietary fiber in childhood. The Journal of Pediatrics, 149 (5): S121-S131. COBISS Code 1.01 Agrovoc descriptors: scaphoideus titanus, pest insects, vineyards, grapevines, vitis vinifera, pest insects, pest surveys, surveys, monitoring, data collection, traps, pest control equipment, plant nurseries Agris category code: h10 Migration of Scaphoideus titanus Ball from the surrounding vineyards into the nursery Primož GRIŽON1, Gabrijel SELJAK2, Irma VUK3,4 Received July 30, 2011; accepted July 23, 2012. Delo je prispelo 30. julija 2011, sprejeto 23. julij 2012. ABSTRACT A one-year study of the mobility of leafhopper Scaphoideus titanus Ball (ST), vector of Flavescence dorée phytoplasma, was conducted in 2009 and included three Slovenian nurseries in the Primorska winegrowing region, as well as two Italian and one Swiss nursery, and was aiming at evaluating the risk of spreading ST with vine propagating material. The presence of ST was monitored by the means of yellow sticky traps that were placed at three distances in the nurseries and the nearby vineyards on three parallel lines (replicates). The traps were equidistantly placed from the nurseries' and vineyards' borders in order to determine the possible distance gradient. The monitoring started in the latest nymphal stages (middle of June) and terminated in the first decade of October. Insecticide treatments with deltamethrin (Decis 2.5 EC) were applied in nurseries, according to the instructions for use and recommendations for suppression of ST. On all Slovenian plots in the vineyards, the population level of ST was high (1796 adults in average / vineyard or 18 adults per trap / week), which indicated a great migration potential of the vector towards the nurseries. Catches were very low (54 adults in average / nursery or 0.4 adults / trap / week) on two nurseries' plots (Lože and Slap), although high numbers of ST adults were caught in the adjacent untreated vineyards. On the Poreče nursery plot, insecticide treatments were not sufficient to avoid high numbers of ST catches (in total 481 adults or 3 adults / trap / week). This could be related to the sub-optimal timing of the first insecticide treatment and/or migration of adults from two nearby untreated vineyards located at a distance of 70 and 150 m. The distance between the nurseries and vineyards did not affect ST catches in the nurseries. Key words: Scaphopideus titanus, Flavescence Dorée, migration, nursery IZVLEČEK MIGRACIJA AMERIŠKEGA ŠKRŽATKA (Scaphoideus titanus Ball) IZ BLIŽNJIH VINOGRADOV V TRSNICO Z namenom preučitve nevarnosti širjenja prenašalca zlate trsne rumenice z razmnoževalnim materialom vinske trte smo v letu 2009 izvedli raziskavo mobilnosti ameriškega škržatka (Scaphoideus titanus Ball) (ST) v treh trsnicah v vinorodni deželi Primorska. V manjšem obsegu je bil poskus izveden tudi pri partnerskih institucijah v Italiji in Švici. Zastopanost in nalet ST smo ugotavljali z rumenimi lepljivimi ploščami, ki so bile postavljene na treh različnih razdaljah od roba trsnice in vinogradov v 3 vzporednih ponovitvah. S postavitvijo lepljivih plošč v enakomernih razmakih od roba trsnice in vinogradov v globino smo želeli ugotoviti morebitni gradient naleta. Z monitoringom naleta smo začeli, ko je bil škodljivec v 5. stadiju ličinke (sredi junija) in ga zaključili v prvi dekadi oktobra. Tretiranje z deltametrinom (Decis 2.5 EC) je bilo izvedeno v trsnici, skladno z navodili za uporabo insekticida in s priporočili za zatiranje ST. Populacija ST v vinogradih je bila na vseh treh lokacija v Sloveniji visoka (v povprečju 1796 odraslih osebkov / vinograd oziroma 18 osebkov / ploščo / teden), kar je predstavljalo velik migracijski potencial prenašalca proti trsnicam. Kljub visoki populaciji ST v bližnjih vinogradih je bilo število ujetih ST v trsnicah na lokaciji Slap in Lože nizko (v povprečju 54 osebkov / trsnico oziroma 0,4 osebka / ploščo / teden). Število ujetih odraslih osebkov na lokaciji Poreče je bilo kljub tretiranju z insekticidom visoko (skupno 481 osebkov ali 3 osebki / ploščo / teden). Vzrok za to gre iskati v neustreznem času prvega tretiranja z insekticidom ali v dodatnem naletu ST iz bližnjih vinogradov, ki so bili oddaljeni 70 in 150 m. Razdalja med trsnico in vinogradom ni vplivala na število ujetih ST v trsnici. Ključne besede: ameriški škržatek, zlata trsna rumenica, migracija, trsnica 1 B. Sc., Ministry of Agriculture and the Environment, Phytosanitary Administration of the Republic of Slovenia, Dunajska 22, SI-1000 Ljubljana, Slovenia; primoz.grizon@gov.si 2 M. Sc., Chamber of Agriculture and Forestry of Slovenia, Agriculture and Forestry Service Nova Gorica, Department for Plant Protection, Pri hrastu 18, SI-5000 Nova Gorica, Slovenia; 3 Ph. D., University of Primorska, Science and Research Center of Koper,Institute for Mediterranean Agriculture and Olive Growing, Garibaldijeva 1, SI-6000 Koper, Slovenia; 4 University of Primorska, Faculty of Mathematics, Natural Sciences and Information Technologies, Glagoljaška 8, SI-6000 Koper, Slovenia; 1 INTRODUCTION The efficacy of insecticide treatments against Scaphoideus titanus Ball (ST) (Hemiptera, Cicadellidae), the vector of Flavescence Dorée phytoplasma (FD), in nurseries depends on the term of treatment regarding the vector's development stage, on the proportion of its mortality, insecticide residues on plants and on the migration of adults from the surrounding vineyards. The previous pesticide registration against ST considered only the situation in spacious vineyards, but did not make any allowances for small-sized nurseries (Boudon-Padieu, 2003). This aspect has to be considered also in adopting a suitable insecticide treatment program. Also the distances between vineyards and nurseries and the mobility range of ST are crucial for determining the risk of spread of ST with the vine grafted plants. ST, a Nearctic leafhopper, was introduced into Europe from the North America before 1958. This univoltine species overwinters in the egg stage. Eggs are deposited into the bark of two or more years old vine branches (Vidano, 1964), rarely also in one-year branches. Nymphs start emerging in the second half of May and adults occur in mid-summer (in the Slovenian climate, at the end of June). They feed exclusively on Vitis spp. and cause indirect damages by transmitting FD from infected vines. Although insecticide treatment against FD vectors is mandatory to prevent the progression of the disease, new contaminations may occur with the movement of infested planting material or ST migrations (Boudon-Padeau et al, 2005). The movement of ST is rather limited to the vine's canopy and is not very likely to fly for more than 2.50 m in high (Lessio F., Alma A., 2004). Seasonal and daily fly of ST is partly influenced by increased temperatures and humidity (Lessio F., Alma A., 2004). In order to determine the risk of FD vector-spreading with the planting material, a one-year study of the mobility of ST was conducted in 2009 in three nurseries in the Slovenian Primorska winegrowing region. The occurrence of ST was monitored using yellow sticky traps. They were placed at three distances in the nurseries and the nearby vineyards in three parallel lines (replicates). The traps were equidistantly placed from the nurseries' and vineyards' borders in order to determine the possible distance gradient. The main part of this study was carried out in Slovenia, where ST is widely spread in all winegrowing regions and the population rates in some vineyards were still fairly large. A small-scale experiment was also conducted in Italy and Switzerland. The objective of the work was to evaluate the effectiveness of insecticide treatments against ST adults in nurseries in order to reduce the risk of immigration of adults from the nearby vineyards. 2 MATERIALS AND METHODS 2.1 Slovenian trials In Slovenia, the monitoring was carried out in 2009 at three locations in the Primorska winegrowing region, winegrowing district of Vipava valley (Slap - 45° 50' 73,55" N, 13° 56' 31,57" E, 99 m altitude; Lože - 45° 49' 52,80" N, 13° 56' 43,68" E, 109 m altitude; Poreče - 45° 50' 57,72" N, 13° 56' 20,30" E, 95 m altitude) with four evaluating plots. Distances between the vineyards and nurseries were different, because the major part of vineyards were grown on hilly sides, while nurseries were situated along the river Vipava. Distances between nurseries and vineyards included in experimental plots are shown in the Table 1. Table 1: Sizes of experimental plots and distances between them Location (size) Vineyard nr. 1 Vineyard nr. 2 1. Slap Nursery (0.8 ha) 126 m 188 m Vineyard nr. 1 (0.65 ha) / Vineyard nr. 2 (2.0 ha) / 2. Poreče Nursery (4.5 ha) 150 m 70 m Vineyard nr. 1 (0.5 ha) / Vineyard nr. 2 (1.1 ha) / 3. Lože Nursery nr. 1 (2.5 ha) 18 m Nursery nr. 2 (0.6 ha) 18 m Vineyard nr. 1 (2.2 ha) / Vineyard nr. 2 (0.43 ha) / Except for the second location where a tree-barrier was grown between the nursery and vineyards, no other spatial obstacles were noticed. Yellow sticky traps (Unichem, 17 x 24 cm) were placed on the plots on 17 June. The traps were placed on the nurseries' and vineyards' edges and in at least three parallel lines (replications). They were placed on the inner side of borders, considering the distance of 10 m between traps. Replications were designated in order to cover the whole area of the vector's mobility; distances between them were 20 m. In vineyards, planted with varieties Merlot, Sauvignon and Cabernet sauvignon, traps were attached with a wire inside the leaf canopy between 1.3 and 1.8 m altitude, depended on the growing type. In nurseries, traps were fixed on 0.5 m long iron stakes. The traps were checked weekly and replaced every three weeks. The monitoring was finished on 8 October. In nurseries, two insecticide treatments against ST were applied. Application data are given in Table 2. Table 2: Data of insecticide treatments in nurseries in Slovenian experiment in 2009 Plot First treatment Second treatment Slap 13. 7. 6. 8. Poreče 9. 7. 31. 7. Lože 20. 7. 7. 8. For all treatments, the insecticide deltametrin (Decis 2.5 EC) in dosage 0.5 L of the product per hectare was used. Data analysis Data were analyzed using nested analysis of variance, where time of sampling were nested within trap distance from border, distance were nested within a plot use (nursery and vineyard), and plot use were nested in location. With this analysis the amount of variability contributed by each factors were estimated. Analysis was performed using STATGRAPHIC 5.0 statistical software. A small-scale experiment was conducted also in Switzerland (one plot) and Italy (two plots). In order to facilitate trial activities and compare results between the three countries, a common protocol had been established before starting the activities. 2.2 Italian trials The experiment performed by the Italian partner (IVC) was done on two plots (Pordenone - 46° 2' 48" N, 12° 52' 23" E, 70 m altitude and Verona - 45° 33' 19" N; 10° 46' 42" E; 200 m altitude). The trials started on 16 June 2009 in Verona and on 30 June 2009 in Pordenone, and were finished on 1 October. Insecticide treatments were applied in nurseries and in vineyards. The period of application as well as the number of treatments was different for the locations, as presented here below: Pordenone Vineyard - four treatments (18 April -deltametrin, 23 May indoxacarb -, 26 June and 21 July chlorpyrifos ethyl). Nursery - three treatments (deltametrin, chlorpyrifos ethyl). Verona Vineyard - one treatment (chlorpyrifos methyl - 14 July). Nursery - seven treatments (20 May - fenazaquin, 29 May - spinosad, 10 June - chlorpyrifos ethyl, 25 June - spinosad, 10 July, 30 July and 20 August - chlorpyrifos ethyl) 2.3 The Swiss trial A small-scale experiment was carried out on one plot (Anieres - 6° 13' 23,5" E, 46° 16' 24,9" N, 412 m altitude). Traps were set on 3 July 2009 and the trial finished on 5 October. Two insecticide treatments against the leafhopper were applied only in the nursery: on 13 July and 27 July. The insecticide used was lambda-cyhalotrine (Kararate with Zeon Technology (9.43% 100 g/l) in dosage 1.2 l/ha. 3 RESULTS 3.1 Slovenian trials On all three Slovenian plots, the population level of ST in vineyards was very high, which indicates a high immigration potential of the vector towards the nurseries. It should also be stressed that all Slovenian experimental locations are exposed to frequent and strong NO-SW winds that may influence the movement direction and distance of ST. Table 3: Results from nested ANOVA analyses of ST catches Source Sum of Df Mean F Variance % variance squares square component component Location 6640.6 2 3320.30 0.12 0.00 0.00 Manner of land use 82043.1 3 27347.70 23.34 ** 116.86 28.75 Trap distance from border 16403.7 14 1171.69 1.90 * 8.64 2.13 Time of sampling Error 172895.0 280 617.48 3.34 ** 96.14 23.65 194083.0 1050 184.84 184.84 45.47 Significance of F values indicated as follows: *p < 0.05; **p < 0.01 The results of nested ANOVA indicate that manner of land use and time of sampling contributes significantly (p < 0.01, F statistic) to the total variance of number of ST. Manner of land use contribute 28.75% of the total variation, and time of 01 f\ sampling contributed 23.65%. The large variance component for the error (45.47%) indicates large variation among replicates within time of sampling. Trap distance from border is significant at p < 0.05, but not at p < 0.01 and contribute only 2.13% of the total variation. Slap location 14,0 12,0 10,0 8,0 6,0 4,0 2,0 0,0 'IT *T °1T Tl \i I. A A _a I *J □ nu rse ry d vineyard nr.1 □ vineyard nr.2 26.6. 3.7. 9.7. 17. 7. 24.7. 31.7. 7.8. 14.8. 21.8. 28.8. 4.9. 11.9. 18.9. 28.9. 8.10. Figure 1: Number of captured adults of ST per trap and day in location Slap At the first location, the number of captured ST in the nurseries was very low (34 adults in total, 0.0 adults / trap / day) in contrast to the captures in the two vineyards in the neighbourhood, where the average number of adults per trap per day was 0.7 for the vineyard No. 1 and 3.6 for the vineyard No. 2. In this case, the high population rate of ST in vineyards didn't imply the population of ST in the nursery; the reason might be fairly long distances between the nursery and vineyards (126 m and 188 m). Also the position of traps regarding the distance from the nursery edge didn't show differences. Insecticide treatments didn't show reduction of population level, especially the second application of 5. August. Porece locatioin The trial conducted on the second plot revealed a high number of ST captures (481 adults in total or 0.4 adults / trap / day in average) in the nursery, with a pick at the end of July (49% of all captures in the nursery). Since the nursery was treated two times with an insecticide, the high number of ST captures could be explained either by the movement of ST from the neighbourhood untreated vineyards (Vineyard nr. 2) or by insufficient efficacy of the first treatments. After the second treatment (31. July), the population rate in the nursery dropped considerably, but still relatively numerous captures afterwards suggest that one or two additional treatments against ST would be necessary. 6,G 5,G ■ -o 4,G i cp tO 4— O <ü 3,G ■ 2,G 1,G ■ G,G "°Tt fT m li Ji □ nursery □ vineyard nr. 2 □ vineyard nr. 1 iUÄ. 26.6. 3.7. 9.7. 17. 7. 24.7. 31.7. 7.8. 14.8. 21.8. 28.8. 4.9. 11.9. 18.9. 28.9. 8.10. Figure 2: Number of captured adults of ST per trap and day in location Porece The highest number of adults was captured on the traps placed 20 meters from the nursery border (182 adults in total or 0.6 adults / trap / day in average). On traps placed on the border line, the mean capture was 0.4 adults / trap /day. 45% of all adults captured at the end of July were found 20 meters from the border line. Lože location At this location, two different plots were evaluated because of the different position of the vineyards. In contrast to the previous locations, in this case the distance between the nursery and vineyard was quite short (18 m) so that the possibilities for the movement of ST from the adjacent vineyard to the nursery were much more reliable. 9,G -i S,ü -7,Q - rat T3 S5,G H I— 4,G - w > H 0 f 2,G - c Z 1,Q - G,G *r *r *r ÜJ I n nursery nr. 1 d vineyard nr.1 4A 26.6. 3.7. 9.7.17. 7.24.7.31.7. 7.S. 14.S. 21.S. 2S.S. 4.9. 11.9. 18.9. 28.9. 8.1G. Figure 3: Number of captured adults of ST per trap and day in Lože nursery nr. 1 14,0 -, 12,0 H -a 10,0 H cp ro iO 8,0 - 6,0 - 5mm Ljubljana annual 10.2 1368 762 1798 22.3 46°4' N vegetation season 16.5 752 620 1291 14°31' E maximum monthly 23.9 147 154 267 299 m. a. s. l. minimum monthly -2.7 71 6 45 Murska Sobota annual 9.6 805 741 1913 14.6 46°39' N vegetation season 16.1 502 599 1343 16°12' E maximum monthly 19.7 104 148 265 188 m. a. s. l. minimum monthly -1.2 31 4 57 Novo mesto annual 9.9 1147 764 1890 20.0 45°48' N vegetation season 16.1 663 612 1316 15°11' E maximum monthly 19.9 123 152 272 220 m. a. s. l. minimum monthly -0.2 49 5 66 Bilje annual 12.0 1446 842 2102 24.3 45°54' N vegetation season 17.6 754 642 1348 13°38' E maximum monthly 21.7 164 174 279 55 m. a. s. l. minimum monthly 3.0 74 2 96 2.2 Input data 2.2.1. Meteorological data Daily meteorological data (precipitation, wind velocity, minimum relative humidity and potential ETP calculated by Penman-Monteith equation) for the period 1961-2010 for four climatological stations were retrieved from the archives of the Slovenian National Meteorological Service at Slovenian Environment Agency (SEA/ARSO). Table 2: Soil characteristics (SEA/ARSO/AWS, 2010) Tabela 2: Lastnosti tal (SEA/ARSO/AWS, 2010) 2.2.2. Soil data Soil type with low water holding capacity (LWHC) was chosen for the study. The water holding capacity of each layer is represented by field capacity (FC) and wilting point (WP). Detailed description of soil characteristics is available in Table 2. This soil type is typical for agricultural areas on alluvial plains of north-east Slovenia where frequent damage due to agricultural drought is reported. Soil layers Top depth (m) Bottom depth (m) Layer thickness (m) FC (%) WP (%) 1 0.00 0.10 0.10 0.30 0.16 2 0.10 0.37 0.27 0.22 0.12 3 0.37 0.60 0.23 0.31 0.16 Soil texture of superficial layer Depth (m) 0.10 Sand(%) 35 Clay (%) 25 2.2.3 Crop data In general vegetation season in Slovenia begins on the first of April and lasts till the end of September. In the study maize crop was analysed. Phenological data for maize (Zea mays) hybrid 'Cisco', data of rooting zone layers were derived by experimental data (SEA/ARSO/AWS, 2010). Crop coefficient (Kc) is dimensionless coefficient used to calculate ETP requirement for a particular crop from the potential ETP for a reference crop (ET0). Crop coefficients are determined experimentally and take into account leaf area development of the crop and the crop canopy physiology (Australian. 2001). Due to lack of experimental data, data from literature were used (Doorenbos and Kassam, 1986). The phenological development for maize is described by 6 phenological stages. All used data are described in Table 3. Soil depletion fraction for no stress (p) was set to 0.4. Table 3: Maize phenological development rooting depths and crop coefficients (SEA/ARSO/AWS, 2010; Doorenbos and Kassam, 1986) Tabela 3: Fenološki razvoj globin korenin in koeficienti rastlin za koruzo (SEA/ARSO/AWS, 2010; Doorenbos and Kassam, 1986) Stages Date Root depth (m) P A - sowing 20.4. 0.01 0.4 B - third leaf 7.5. 0.20 0.4 C - tasseling 9.7. 0.50 0.4 D - milky ripe 16.8. 0.50 0.4 E - fully ripe 8.10. 0.50 0.4 F - harvest 14.10. 0.50 0.4 Date Kc 30.4. 0.20 7.5. 0.50 11.5. 0.90 28.6. 1.10 9.7. 1.20 16.8. 0.60 20.9. 0.50 2.3 Methods 2.3.1 Water balance Simple surface water balance accumulation (denoted as WB and calculated as difference between precipitation and ETP accumulation) is used as one of drought indicators in this paper. 50 vegetation seasons are available in the database records. In the first part of investigation the 30-day WB was used in comparison to SPI1, following by analysis of 10-day WB and NIR in the second part. 2.3.2 Standardized precipitation index The Standardized Precipitation Index makes it possible to quantify the precipitation anomaly with respect to long time average condition (1971-2000) for a specific month and time scale. The long term precipitation record is fit to a probability distribution, which is then normalised so that the mean (average) SPI for any place and time period is zero. Positive SPI values indicate greater than median precipitation and negative values mean less than median precipitation. Drought is defined when SPI reaches value of -1 or less, while value of 1 or more defines wet spell. Value also classifies severity of drought or wetness (Table 4). SPI is typical meteorological index, the short time scale (1-month; SPI1) and medium-term time scale (6-month; SPI6) have been chosen for the analysis. SPI1, which includes 30 days antecedent precipitation, was calculated for each decade in the vegetation seasons. SPI1 is suitable for detecting the presence, in drought event dynamics, of changes that could be particularly important from agricultural Table 4: Classification of SPI values (McKee et al., 1993) Tabela 3: Razvrstitev vrednosti SPI (McKee in sod.,1993) viewpoint. SPI6 was chosen as indicator of cumulative property of vegetation season since SPI6 - if evaluated in September - covers whole period from early spring to harvest of typical summer crops. SPI value: Drought category 2.00 and above extremely wet 1.50 to 1.99 very wet 1.00 to 1.49 moderately wet -0.99 to 0.99 near normal -1.00 to -1.49 moderately dry -1.50 to -1.99 severely dry -2.00 and less extremely dry Figure 2: Spatial distribution of SPI6 for September 2003 (available at: http://www.dmcsee.org/en/drought monitor/) Slika 2: Prostorska porazdelitev SPI6 za september 2003 (dostopno na: http://www.dmcsee.org/en/drought_monitor/) 2.3.3. WinISAREG model With the aim of obtaining an actual description of the changes expected in the agricultural WB of the locations, the time series of simulated maize consumption were computed by model WinISAREG. Model WinISAREG (Pereira et. al, 2003; Paredes and Pereira, 2010) is a conceptual WB model for simulating crop irrigation schedules at field level and provides calculation of irrigation requirements under optimal and/or water stressed conditions. Besides input meteorological data (precipitation, ETP, wind velocity and minimum relative humidity) for WB calculation model demands crop data, soil data and irrigation option data. Also it is optional to define ground water contribution, water supply restrictions and salinity. In this study, these three parameters were not included. Model includes modul EVAP56 (Pereira et al., 2003) for computation of reference ETP using FAO Penman Monteith method but since ETP calculation is calculated routinely in SEA/ARSO this module was not used. Water balance is performed for a multilayered soil, crop coefficients and root depths at time scale of defined development periods of certain crop. For estimation of crop WB or irrigation, model setting named field, horticultural and tree crops was used. Fixed dates of maize phenological development for year 2010 were set for all the years. According to the experience of Popova and Pereira (2008) it is optional to use the yield response factor Ky that is derived from field data on yields relative to various irrigation and rainfed regimes. The parameter Ky introduces in the WinISAREG model, the relation between ETP deficit caused by water stress and the corresponding yield decrease (Paredes and Pereira, 2010). Unfortunately, data for Slovenia are not available therefore crop coefficients from FAO (Doorenbos and Kassam, 1986) were used in the study and adjusted to the local root depth measurements (SEA/ARSO/AWS, 2010). In our analysis we used value 1.25 for Ky (Doorenbos and Kassam, 1986). The model initializes soil water simulations with initial soil water content provided by user. Initial total available water (TAW) was set on 100 %. Various time steps of model calculation are adopted depending on weather data availability and required output variable. Model simulation was performed in a way to recognize drought periods according to irrigation requirements. Therefore in WinISAREG model Irrigation Simulation Options mode NIR was used. After simulation model provides information on soil WB or irrigation requirements. In our study daily data were used for ten days and seasonal calculations of NIR, which were input for further investigations. 2.3.4. Statistical methods Results of the crop water simulations were compared with the information available in the agrometeorological reports of SEA/ARSO (1960-2010). Dry seasons detected by study were compared to descriptions in the reports. Beside that, yield decrease and damage due to drought described by the reports of statistical office (Statistical... 2010) were included into discussion and results. In order to evaluate trends of WB and evapotranspiration at local scale, linear regression was performed. 3 RESULTS 3.1 Analysis of Standardized Precipitation Index for vegetation seasons 1961-2010 The analysis of the vegetation season time series of SPI6 in the period 1961-2010 shows that from 6 (Novo mesto) to 11 (Bilje) seasons were dry and from 6 (Novo mesto) to 10 (Murska Sobota) seasons were wet. At all locations, except for Bilje, drought in years 2003 and 1992 were detected by SPI6 (Figure 4) as extremely severe. Drought in year 2000 (Ljubljana, Novo mesto, Murska Sobota) and in year 2006 (Bilje) were extreme but more regionalised. The main reason for extreme drought detected by SPI6 in the vegetation period in Bilje region was lack of precipitation. In the period from April to July only 190 mm of rain fall, in comparison to other analysed regions were amount of precipitation was more than 400 mm. Above mentioned years were analysed more in details with all the indicators. According to the fact that SPI6 was not appropriate indicator to detect drought dynamics due to its large internal time scale, SPI1 was calculated in ten day updating intervals during the vegetation seasons. Figure 3: Number of vegetation seasons distributed in SPI6 classes Slika 3: Število vegetacijskih sezon porazdeljenih v SPI6 razrede In the Figure 3 for all the locations number of years in specific SPI class is presented. o LJUBLJANA MURSKA SOBOTA NOVO MESTO BILJE -0.5 -1 -1.5 -2 -25 -3 1979 1967j ♦ 2000 1983* 1971 I 1992 2003 1988 2003 ^ 1983 ♦ 1993 * 2000 * 1971 ♦ 1992 1961 ♦ 1992 ♦ 2009 ♦ 1971 ♦ 2003 ♦ 2000 J1990+.13Z1-11986 1963 198 fr 2007 ♦ 1983 * ♦ 2009 ♦ 1962 ♦ 2006 -3.5 -4 4.5 ♦ 2003 Figure 4: Vegetation seasons classified according to SPI6 in the range of dry years Slika 4: Sušne vegetacijske sezone razvrščene po SPI6 3.2 Analysis of water balance Average 40-year vegetation water balance shows that ETP during vegetation season is mainly covered by precipitation amount, unfavourable only at Murska Sobota (long term water deficit is 104 mm). In the last ten years the circumstances are getting drier which reflects in slightly lower WB in the eastern Slovenia and significant decrease in western Slovenia (Figure 5). Only in Ljubljana region there is a slight increase of WB during vegetation season. In the dormancy small change of WB is in Ljubljana, Novo mesto and Bilje are observed. The largest decrease of WB is in Murska Sobota, 47 mm. The reason for changing water balance is higher ETP rate (more than 5 mm) in the period 2001-2010 increased from 5 to 16 days in comparison to the period 1971-2000 (Figure 6). Figure 5: Average water balance in vegetation season (left) and in dormancy (right) in periods 1971-2010 and 20012010 Slika 5: Dolgoletna povprečja vodne bilance vegetacijski sezoni (levo) in v dormanci (desno) v obdobjih 1971-2010 in 2001-2010 Figure 6: Number of days with ETP > 5 mm in the period 1971-2010 and 2001-2010 in vegetation seasons Slika 6: Število dni z visokim izhlapevanjem, ETP > 5 mm v vegetacijskih sezonah v obdobju 1971-2010 in 20012010 3.3 Drought analysis using Net Irrigation Requirements NIRs show similar pattern at specific locations as SPI6. According to the cumulative frequency of NIR, years in the range between 80 % in 100 % were determined as dry. In Ljubljana years 2003, 2001, 2006, 2000 were detected as dry by NIR but only 2000 and 2003 were detected by SPI6 (Figure 7). Distribution of dry years by NIR does not fit always with the order using SPI6. The best fit is only with extremely dry years. This result was somehow expected; while during extreme droughts in the vegetation season both severe lack of precipitation and increased ETP appear simultaneously, this is not the case in years that are near to normal conditions. Very important impact on the severity of drought is distribution of precipitation (drought in year 2006). Shorter heat waves can be interchanged by wet periods so SPI6 (presenting total precipitation anomaly) and NIR (presenting total irrigation requirements) can show different trends. 300 n 13.7 17.6 21.6 25 5 29.4 33.3 37.3 41 2 45.1 49 52 9 56.9 60.8 64.7 68 6 72.5 76.5 80 4 84.3 88.2 92.2 96 1 cumulative frequency [%] Figure 7: Classification of NIR according to cumulative frequency in Ljubljana in the period 1961-2010 Slika 7: Razvrstitev NIR-a glede na kumulativno frekvenco za Ljubljano v obdobju 1961-2010 3.4 Comparison of SPI1 to 30-day water balance and NIR to 10-day water balance WB, NIR and SPI1 calculations were performed for 10-day periods. Years with extreme droughts are described more in details in sections 3.4.1. Detailed simulations of all indicators are presented in two graphs in Figure 8, 9, 10 and 11. For specific dry vegetation season upper graph represents SPI1 and WB30 describing 30-day weather conditions. In the graph below NIR and WB10 are simulating 10-day circumstances 3.4.1 Case studies - years with extreme droughts SPI1, NIR and WB for 1992, 2000, 2003 and 2006 vegetation seasons are presented in the Figure 8, 9, 10 and 11. 3.4.1.1. Year 1992 The drought in Murska Sobota has started already in spring. It continued in May and affected besides Murska Sobota region also other areas. The agriculture drought damaged maize crops. At the end of May, instable weather with precipitation interrupted the dry spell. Precipitation in the first decade of June moistened the soil. At the end of June second drought appeared. At the end of second decade of June curled leaves of crops have already been noticed in some parts of Slovenia. Drought lasted in Murska Sobota region until the end of August. According to the reports agricultural drought was present also at the other parts in Slovenia, but the most extreme was in region around Murska Sobota. Maize crops on sandy soils were affected the most, from 70 to 90 % of maize crops were damaged due to drought. Most of rainfed agricultural crops ripened forcedly. In Figure 8 SP1, NIR and WB for vegetation season 1992 is presented. According to SPI1 there were two major dry spells, first at the end of May and second lasting through the whole August, while according to WB and NIR there were three periods of drought appearing in May, June and August. Magnitude of drought in August was classified as the most severe. SPI results imply the lack of precipitation was the highest in Murska Sobota. Comparison of SPI for all sites shows the lowest drought severity in Bilje. The highest magnitude and the longest duration of drought are identified indices. in Murska Sobota also by WB and NIR Figure 8: Ten day SPI1, WB30, NIR and WB10 values for vegetation season 1992 Slika 8: Vrednosti SPI1, WB30, NIR in WB10, računane na vsako dekado za vegetacijsko sezono 1992 3.4.1.2. Year 2000 Due to the lack of precipitation during the winter and early spring, the first interval of agricultural drought was detected in the middle of April. Consequently the winter crops were delayed in the tillering stage. Results of drought indices calculation for the year 2000 are shown in Figure 9 and confirmed by agrometeorological report survey. The second dry interval appeared in the summer in the major agricultural areas in Slovenia. SPI1 shows period of drought from the beginning of May till the middle of July for Novo mesto. Regarding to SPI1 two short periods with lower drought severity in summer appeared also at other sites. WB for vegetation season is mostly negative with few exceptions at particular individual site. NIR is resulting in a way complementary to WB, as negative soil WB demands irrigation. The short wet interval with positive WB was in the second decade of July. This was the most severe agricultural drought in the 10-year period from 1990 to 2000. Drought affected most agricultural plants in the most sensitive phenological stages: maize crops in the tasseling and pollinating stages, setting of cobs and ripening. By the end of June the agricultural drought had halved the normally expected yield, while at the end of the first third of July the consequences attained the extent of a natural disaster. The most distressed regions were the agricultural areas around Novo mesto and Murska Sobota. The maximum damage was recorded in maize crops, which represents the major crop in the agricultural areas of Murska Sobota. Crop yield in the areas of Murska Sobota, Novo mesto and Bilje was reduced by 20 - 30 %. The drought was terminated by abundant precipitation at all sites in the beginning of September. a ¿r Figure 9: Ten day SPI1, WB30, NIR and WB10 values for vegetation season 2000 Slika 9: Vrednosti SPI1, WB30, NIR in WB10, računane na vsako dekado za vegetacijsko sezono 2000 3.4.1.3 Year 2003 Drought in 2003 lasted from end of April up to second decade of July. It affected the whole country. The damage due to drought attained the extent of a natural disaster which ranked amongst the worst in the previous 50 years. Vegetation season of the year 2003 using SPI1, WB and NIR indices are presented in Figure 10. SPI1 corresponds to precipitation conditions for all sites, continuously below zero SPI value in the major part of the vegetation season. SPI1 indicates severe drought at all sites at the beginning of April. Another drought period for all sites except for Murska Sobota started in the second decade of May. According to SPI1 in Bilje drought lasted till the second decade in August, in Novo mesto till the first decade of July, in Ljubljana dry spell also lasted till the first decade of July but was interrupted at the beginning of June. In Murska Sobota drought lasted from the second decade of June till the end of July. The soil water reservoir was not refilled until abundant precipitation in September. However, the WB equilibrium was not restored due to enormous summer water deficit until the end of the year. The consequences of summer drought were detected also in earlier timing of autumn phenological phases. Long standing water stress heavily influenced the development of maize. Maize grown on shallow and sandy soils visibly lagged behind the normal growth. The damage was assessed to more than 128 million €. It attained the extent of a heavy natural disaster. About 83 % of Slovenian agricultural area was distressed (Statistical..., 2010). The drought characteristics were detected also by WB. NIR corresponds to negative WB. With respect to WB values and NIR drought severity was the highest in Bilje following by Murska Sobota and Novo mesto. Figure 10: Ten day SPI1, WB30, NIR and WB10 values for vegetation season 2003 Slika 10: Vrednosti SPI1, WB30, NIR in WB10, računane na vsako dekado za vegetacijsko sezono 2003 3.4.1.4 Year 2006 In the last decade of June 2006 the distinctive water shortage by agriculture crops was detected due to the lack of precipitation. Drought was intensified till the end of July at whole Slovenia but the most seriously in the area of Bilje and Novo mesto. At the beginning of August the abundant precipitation ceased two months lasting summer drought. At Bilje region maximum damage due to drought was recorded. Maize yield was reduced by 40 to 90 %. According to SPI1 drought has not appeared in Murska Sobota in July which neglected the real situation. On the contrary, WB and NIR confirmed dry signal in June and July. SPI1 and NIR indicate the maximum SPI1 and the highest values of irrigation requirements among all analysed years in Bilje. 1/4 11/4 111/4 1/5 11/5 111/5 1/6 11/6 111/6 1/7 11/7 111/7 1/8 11/8 111/8 1/9 11/9 111/9 40 -- ;-20 - -40 -- -60 -- EEE3 VVB30 Ljubljana EE23 VVB30 Novo mesto -SP11 Ljubljana -SP11 Novo mesto 3VVB30 Murska Sobota i VVB30 Bilje - SP11 Murska Sobota -SPI1 Bilje CEB VVB10 Ljubljana ^WB10 Murska Sobota EE3VVB10 Novo mesto a VVB 10 Bilje -NIR Ljubljana -NIR Murska Sobota -NIR Novo mesto -NIR Bilje I/4 H/4 I/5 H/5 HI/5 I/6 H/6 HI/6 I/7 H/7 HI/7 I/8 H/8 III/8 I/9 Figure 11: Ten day SPI1, WB30, NIR and WB10 values for vegetation season 2006 Slika 11: Vrednosti SPI1, WB30, NIR in WB10, računane na vsako dekado za vegetacijsko sezono 2006 3.5. Data verification Data verification was strictly limited to maize in the vegetation season. Dryness (defined by NIR and SPI6) in the vegetation season was checked by reports about drought agricultural impacts reported in the bulletins of the SEA/ARSO. Only years detected as dry by SPI6 and NIR were included in the evaluation process. In Table comparison with reports for dry years is presented. Only year 2003 was confirmed with both indicators and reports. Table 5: Classification of dry years with drought within vegetation season detected by SPI6, NIR and comparison with reports of SEA/ARSO (+ drought, - no drought) for Ljubljana (LJ), Murska Sobota (MS), Novo mesto (NM) and Bilje (BI) Tabela 4: Razvrstitev suhih let, s sušo v vegetacijski sezoni, ugotovljeno z indeksi SPI6 in NIR ter primerjano z arhivom ARSO (+ suša, - ni suše) za Ljubljano (LJ), Mursko Soboto (MS), Novo mesto (NM) in Bilje (BI) SPIS MIR ARSO LJ M 5 NM BI LJ MS NM BI LJ MS NM BI REMARKS 1961 - - + - - - - - - - - - NM - precipitation below the average (SPI6), but not low enough for drought 1962 - - - + - - - - - - - + Bl - NIR value slightly below chosen threshold short - term drought 1963 - - - + - - - - - - - - Bl - precipitation below the average (SPi6), but not low enough for drought 1967 + - - - - - - - - - - - LJ - precipitation below the average, but not low enough for drought 1971 + + + + + + - - + + + + NM - NIR value slightly below chosen threshold short - term drought: Bl - wet first three months of vegetative season 1973 - - - - - - ■f - - - + - NM - precipitation (SPI6) near threshold for drought 1976 - - - - - - + - - - + - NM - precipitation on the dry side of normall range (SPIE) 1979 + - - - - - + - + - + - LJ ■ short ■ term drought (according to SEA/ARSO); NM - 3PI6 near threshold for drought 1981 - - - - - - - - + - - Bl ■ irregularly distributon of precipitation large amount of rain in June (130 mm in 3 days) and September 1983 + + - + + + - - + + - + Bl - hot and dry condition at the time of polination influenced on harvest 1985 - - - + - - - + - - - + 1986 - - - + - - - + - - - + 1988 - + - - - - - + - + LJ ■ precipitation near normal value, but not enough for maize: MS - NIR value slightly below chosen threshold; El ■ hot and dry condition at the time of polination influenced on haivest 1990 - - - + - - - - - - - + Bl - NIR value slightly below chosen threshold short ■ term drought 1991 + - - - + - - - + - - - 1992 + + + - + + - - + + + - NM - NIR value slightly below chosen threshold, short ■ term drought 1993 - + - - - + + - - + + - NM - precipitation below the average (SPI6), but not low enough for drought 1994 - - - - - - - + - - - + Bl ■ precipitation below the average (SPI6). but not low enough for drought 1996 - - - - - - + - - - + - NM - precipitation below the average (SPI6), but not low enough for drought 2000 + + + - + + -5- + + + + + Bl ■ precipitation below the average (SPI6), but not low enough for drought 2001 - - - - + + + + + + + + a large amount of precipitation in September affect SPI6 2003 + + + + + + + + + + + 2004 - - - - - - - + - - - - Bl - NIR value equal to chosen threshold 2006 - - - + - + + - + + LJ and NM - a large amount of precipitation in August affect on SPI6 2007 - - - + - + - + - + - + MS - a large amount of precipitation in September affect on SPI6 2009 - - + + - - - + - - + + NM - NIR value slightly below chosen threshold 2010 - - - - + + + LJ. MS. NM - NIR value near chosen threshold 3.6. Trend analysis Additionally time trends of water components were performed for the period 1961-2010. The hypothesis that cumulative ETP and number of days with high ETP rate (more than 5 mm/day) in the vegetation season are increasing was confirmed. The trend is statistically significant at all locations. The largest increase was recorded in Bilje, absolute change around 7 %/10 years and the minor increase in Novo mesto with almost 2 %/10 years. At all locations the noticeable increase of crop water consumption in last ten years is observed, from 20 to 40 %. The slight trend of precipitation decrease during vegetation season was detected. The trend analysis of vegetation season precipitation amount showed that the average trend is around 1 %/10 years at all locations. The WB during the vegetation season showed trend to more intense water deficit in last ten years, only in Ljubljana WB slightly increases. Table 6: Absolute and relative change of ETP and NIR in the period 1961-2010 Tabela 5: Absolutna in relativna sprememba ETP in NIR v obdobju 1961-2010 Ljubljana Murska Sobota Novo mesto Bilje* absolute change ETP in (mm/10 years) 14.6 20.4 10.1 42.5 vegetation relative change season (%/10 years) +2.4 ** +3 4 ** +1.7 +6.6 ** absolute change ETP > 5 mm (NOD/10 years) 4.1 4.6 3.6 10.0 in vegetation relative change season (%/10 years) +18.6 ** +31.7 ** +18.1 ** +41.1 ** absolute change NIR in (mm/10 years) 13.9 14.4 11.8 26.7 vegetation relative change season (%/10 years) +8.8 +8.7 +7.2 % +14.0 NOD ... Number of days * ... Period 1962-2010 ** ... Statistically significant SPI6 is showing increase of dry vegetation season in the period 2001-2010 in comparison to the period 1971-1990 in Novo mesto and Bilje. In Ljubljana and Murska Sobota SPI6 shows even decrease. NIR trends for maize during the vegetation season vary a lot, but it is common that all the locations are characterised by the increase of the deficit for 8 - 14 %/10 years (Table 6). In last ten years (2001-2010) in comparison to the reference period (1971-2010) on average increased for 23% in the range from 17 to 38 % (Table 7). Table 7: Average NIR in the period 1971-2000 and relative change of NIR in the period 2001-2010 in comparison to the period 1971-2000 Tabela 6: Povprečni NIR v obdobju 1971-2000 in relativna sprememba NIR-a v obdobju 2001-2010 v primerjavi z obdobjem 1971-2000 LJUBLJANA MURSKA SOBOTA NOVO MESTO BILJE 1971-2000 2001-2010 1971-2000 2001-2010 1971-2000 2001-2010 1971-2000 2001-2010 NIR (mm) 158 +17 % 166 +20 % 163 +17 % 191 +38 % 4 DISCUSSION In general, concern about rising frequency and impacts of drought is justified. Economical costs are increasing. In year 2000 almost 79 million € damage due to drought was recorded, in 2001 almost 42 million €, in 2003 more than 128 million € and in 2006 almost 50 million €. A drought monitoring and early warning systems should be established to provide information on the formation, development and end of drought. In our study SPI as indicator was less suitable for detecting agricultural drought than crop WB and NIR. In order to monitor the occurrence and development of agricultural drought efficiently and provide information on the strength and range of drought more indicators should be included in the monitoring. For agricultural drought monitoring only integrated tools as plant - soil - climate models will dynamically monitor occurrence and evolution of drought over specific region. 5 REFERENCES Australian National Committee on Irrigation and Drainage, 2001. Rural Water Industry Terminology and Units. 2nd edition, Australia Doorenbos, J.; Kassam, A.H. 1986. Yield response to water. Irrigation and Drainage paper 33, FAO, Rome. DMCSEE. 2011. Drought management center for SE Europe. Drought monitor. Drought bulletins and maps. Available at:. http://www.dmcsee.org/drought_monitor Heim, Jr., R. R. 2002. A review of Twentieth-Century Drought Indices Used in the United States, pp. 1149 - 1165 McKee, T. B.; Doesken, N. J. and Kleist, J. 1995. Drought monitoring with multiple time scales. Preprints, 9th Conference on Applied Climatology: pp. 233-236. McKee, T. B.; Doesken, N. J. and Kleist, J. 1993. The relationship of drought frequency and duration to time scales. Preprints, 8th Conference on Applied Climatology, pp. 179 - 184. Paredes, P.; Pereira, L. S. 2010. Water balance and irrigation scheduling simulation model The WinISAREG model. Biosystem Engineering, Institute of Agronomy, Technical University of Lisbon, Lisbon. Pereira, L. S.; Teodoro, P. R.; Rodrigues, P. N.; Teixeira, J. L. 2003. Irrigation scheduling simulation: the model ISAREG. Popova, Z.; Pereira, L. S. 2008. Irrigation scheduling for furrow-irrigated maize under climate uncertainties in the Thrace plain, Bulgaria. Biosystems Engineering 99, pp. 587 - 597. Rossi, G.; Cancelliere, A.; Pereira, L. S.; Oweis, T.; Shatanawi, M.; Zairi, A. (Eds.) Tools for Drought Mitigation in Mediterranean Regions. Kluver, Dordrecht, pp. 161-180. SEA/ARSO/AWS. 2010. Modeliranje vodne bilance na izbranih kmetijskih kulturah na Dravskem in Ptujskem polju. Projektna dokumentacija projekta Alp Water Scarce v sodelovanju s KGZ MB. SEA/ARSO. 2010. Agrometeorološki mesečni in dekadni bilteni 1961-2009. Ljubljana. SEA/ARSO. 2010. Meteorological Annuals -Agrometeorology 1961-2010. Ljubljana. Statistical Office of the Republic of Slovenia (SURS). 2010. Ocenjena škoda, ki so jo povzročile naravne nesreče: http://www.stat.si/pxweb/Database/Okolj e/27_okolj e/05_Nesrece/27089_ocenjena_skoda/27089_ocenj ena_skoda.asp (10.12.2010). COBISS Code 1.02 Agrovoc descriptors: coccidae, ecology, vitis vinifera, grapevines, vineyards, taxonomy, biosystematics, damage, crop yield, pest insects, insect control, pest control, vectors, hosts, disease transmission, insecticides, biological control, control methods Agris category code: h10, h20 Kaparji (Hemiptera: Coccoidea) vinske trte (Vitis vinifera L.) v Sloveniji in možnosti njihovega biotičnega zatiranja Melita ŠTRUKELJ1, Irena MAVRIČ PLEŠKO2, Gregor UREK3, Stanislav TRDAN4 Delo je prispelo 04. julija 2012, sprejeto 28. avgusta 2012. Received July 04, 2012; accepted August 28, 2012. IZVLEČEK V Sloveniji se na vinski trti pojavljajo kaparji Neopulvinaria innumerabilis, Pulvinaria vitis, Parthenolecanium corni in Planococcus ficus. Te žuželke sesajo rastlinski sok in povzročajo prezgodnje odpadanje listov in bolezenske okužbe grozdov, kar vpliva na kakovost pridelka. Kaparji so tudi pomembni prenašalci rastlinskih virusov. Vrsti P. vitis in P. corni sta razširjena po vsej Sloveniji, vrsta N. innumerabilis v vinogradih na Primorskem, vrsto P. ficus pa največkrat najdemo v zavarovanih prostorih. Običajno kaparje zatiramo z uporabo insekticidov, vendar so sodobne strategije varstva rastlin usmerjene v naravi prijaznejše načine, kot sta mehansko in biotično zatiranje škodljivcev. Pri nas biotično zatiranje kaparjev še ni dobro raziskano, čeprav se je v srednji Evropi že izkazalo za uspešno. Ključne besede: kaparji, Coccidae, Pseudococcidae, sistematika, morfologija, bionomija, škodljivost, zatiranje, biotično varstvo ABSTRACT SOFT SCALES AND MEALYBUGS (Hemiptera: Coccoidea) ON GRAPEVINE (Vitis vinifera L.) IN SLOVENIA AND THE POSSIBILITIES OF THEIR BIOLOGICAL CONTROL In Slovenia Neopulvinaria innumerabilis, Pulvinaria vitis, Parthenolecanium corni and Planococcus ficus have been identified on grapevine. These insects cause earlier discolorations on the leaves and defoliation and consequently cause poor growth of plants and reduction of yield and crop quality. They can also transmit important plant viruses. P. vitis and P. corni are widespread in Slovenia. N. innumerabilis was found in vineyards of Primorska, while P. ficus was found mainly in greenhouses. Because of their great economic influence insecticides are used for their control. Natural enemies make a significant contribution to biological control of these insects. The biological control of scale insects is not well studied in Slovenia, although it has proved to be successful in Central Europe. Key words: scale insects, mealybugs, Coccidae, Pseudococcidae, systematics, morphology, bionomics, damage, control, biological control 1 mlada raziskovalka, Kmetijski inštitut Slovenije, Hacquetova ulica 17, SI-1001 Ljubljana, e-mail: melita.strukelj@kis.si 2 dr., Kmetijski inštitut Slovenije, Hacquetova ulica 17, SI-1001 Ljubljana 3 doc. dr., Kmetijski inštitut Slovenije, Hacquetova ulica 17, SI-1001 Ljubljana 4 izr. prof., dr., Biotehniška fakulteta, Oddelek za agronomijo, Jamnikarjeva 101, SI-1111 Ljubljana 1 UVOD Kaparji so tujerodne fitofagne žuželke, ki jih uvrščamo v red polkrilcev (Hemiptera), čeprav so bili do nedavnega uvrščeni v red enakokrilcev (Homoptera). Kaparje uvrščamo v naddružino Coccoidea (podred Sternorrhyncha), ki vsebuje 48 družin (Ben-Dov in sod., 2012). Predstavnike devetih družin so potrdili tudi v Sloveniji (Seljak, 2010). Tako v svetu kot pri nas so vrstno najštevilčnejše tri družine, Diaspididae (2479 vrst), Pseudococcidae (2231 vrst) in Coccidae (1133 vrst) (Ben-Dov in sod., 2012). V Sloveniji je bilo na različnih gostiteljskih rastlinah najdenih 43 vrst iz družine Diaspididae, 26 vrst iz družine Coccidae in 18 vrst iz družine Pseudococcidae. Po doslej zbranih podatkih najdemo na vinski trti pri nas le predstavnike zadnjih dveh družin (Seljak, 2010). V zadnjih 20 letih so v Sloveniji zabeležili porast tujerodnih organizmov. Kaparji predstavljajo kar 41,1 % (37 vrst) vseh polkrilcev, ki so bili v Slovenijo vneseni ali pa so se postopno razširili na to ozemlje (Seljak, 2011). Na splošno so škodljivi predvsem na sadnem drevju, grmičevju in rastlinah v zavarovanih prostorih (Kosztarb in Kozar, 1988). Hranijo se z rastlinskim sokom in s tem oslabijo rastlino, povzročijo razbarvanje in prezgodnje odpadanje listov, deformacije vej, mnogokrat pa so tudi prenašalci rastlinskih virusov (Kosztarb in Kozar, 1988; Golino in sod., 1999, 2002; Martelli in sod., 2002; Sim in sod., 2003). Posredna škoda, ki jo povzročajo, je izločanje medene rose, kamor se naselijo glive sajavosti (Hamon, 1984; Kosztarb in Kozar, 1988; Gullan in Martin, 2009). Primarno so kaparji škodljive žuželke, vendar so nekatere vrste med njimi tudi vir mnogih uporabnih snovi, ki jih s pridom izrabljajo druge žuželčje vrste in ljudje. Kaparji poleg medene rose proizvajajo tudi vosek in naravna barvila (Lagowska in Golan, 2009). Pogosto so predmet preučevanja ekologov in evolucijskih biologov zaradi njihovega simbiontskega odnosa z mravljami. S tem ko mravlje nabirajo medeno roso, odstranijo snovi, potrebne za razvoj gliv sajavosti. Te glive so škodljive ne samo rastlinam, ampak tudi kaparjem, saj jih lahko okužijo in povzročijo njihov pogin (Kosztarb in Kozar, 1988). Za nekatere vrste kaparjev je znano, da imajo mutualistični odnos z neželastimi čebelami (Hymenoptera: Apidae: Meliponinae). Čebelam je medena rosa vir hrane, poleg tega s tem dobijo tudi dodaten vosek za gradnjo satja (Camargo in Perdo, 2002). Po podatkih Seljaka in Žežline (2007) se v Sloveniji na vinski trti pojavljajo štiri vrste kaparjev. Veliki trtni kapar (Neopulvinaria innumerabilis Rathvon), navadni trtni kapar (Pulvinaria vitis L.) in češpljev kapar (Parthenolecanium corni [Bouché]) sodijo v družino Coccidae, medtem ko smokvinega volnatega kaparja (Planococcus ficus Signoret) uvrščamo v družino Pseudococcidae. Poleg naštetih, je na vinski trti gospodarsko škodljiv tudi kapar Parthenolecanium persicae Fabricius (Pellizzari, 1997). Vendar ga pri nas na tej rastlinski vrsti še niso potrdili (Seljak, 2010), našli pa so ga na vinski trti v Istri na Hrvaškem (Masten-Milek in sod., 2007). Navadni trtni kapar in češpljev kapar sta razširjena po vsej Sloveniji, veliki trtni kapar pa le v vinogradih na Primorskem, kjer v bolj vročih letih najdemo tudi smokvinega volnatega kaparja. Ta vrsta je tropskega oz. subtropskega izvora, zato o njeni škodi v Sloveniji le redko poročajo, saj preživi samo v zavarovanih prostorih. Pogosteje se pojavlja v rastlinjakih na baznem materialu vinske trte kot pa na prostem (Seljak in Žežlina, 2007). 2 TELESNA ZGRADBA IN RAZVOJNI KROG KAPARJEV (COCCIDAE IN PSEUDOCOCCIDAE) Pri kaparjih iz družin Coccidae in Pseudococcidae je močno izražen spolni dimorfizem. Klasifikacija temelji večinoma na morfoloških lastnostih odraslih samic (Kondo in sod., 2008). Segmentacija pri samicah ni vedno razločna, vedno so brez kril, telo je navadno ovalne oblike, noge so petčlenaste in dobro razvite. Za njih je značilna neotenija, oziroma sposobnost razmnoževanja samice že na stopnji nimfe (Ben-Dov, 1997; Miller, 2005). Oči so enostavne in navadno zmanjšane v dve majhni obarvani pegi. Tipalke so dobro razvite zod 1 do 16 segmenti ali pa tipalk sploh nimajo. Zadnjična (analna) odprtina je obkrožena s sklerotiziranim analnim obročem, nameščena na zadnjem telesnem obroču (členu). Obdana je s setami ter porami za izločanje voska (Kosztarb in Kozar, 1988). Odrasle samice naddružine Coccoidea lahko živijo od nekaj mesecev do nekaj let (Gullan in Martin, 2009). Samci kaparjev imajo razvito glavo (caput), oprsje (thorax) in zadek (abdomen). Glava je sklerotizirana ter pri družinah Coccidae in Pseudococcidae z vratom jasno ločena od telesa. Tipalke (antennae) so sestavljene iz osmih do desetih členov, nitaste oblike s številnimi setami. Tip oči se med družinami razlikuje, ustnega aparata pa samci nimajo. Telo je sestavljeno iz devetih delov, s štirimi dihalnimi odprtinami vzdolž trupa, razvit je en par kril in močno oščetinjene dolge, vitke pet-člene noge s kaveljcem. Na zadku imajo dolge filamentozne sete. Življenjska doba odraslih samcev je od nekaj ur do nekaj dni po preobrazbi. V tem času je njihova glavna naloga najti samico in jo oploditi (Kosztarb in Kozar, 1988). Število rodov na leto je vrstno značilno. Medtem ko imajo v srednji Evropi najpogosteje en rod letno, je za tropske vrste značilnih več rodov letno (Kosztarb in Kozar, 1988). Samice so hemimetabolne žuželke in imajo najmanj dva razvojna stadija, medtem ko gredo samci skozi pet stopenj holometabolnega razvoja: dva nimfalna stadija, predbubo, bubo in končno fazo odraslega osebka (Kosztarb in Kozar, 1988; Williams, 1997; Miller in sod., 2007). Novo izlegle nimfe kaparjev niso zavarovane z voščenim poprhom kot so to odrasle samice, zato so zelo občutljive na insekticide. Kmalu po pojavu se premaknejo na spodnjo stran listov, kjer se ustalijo in hranijo. Pred prehodom v tretji razvojni stadij se samci obdajo z belim voščenim ovojem, kjer se preobrazijo v krilate osebke (Kosztarb in Kozar, 1988). Kaparji se aktivno premikajo v času prve nimfalne stopnje in kot krilati samci po preobrazbi. Premikajo se sicer tudi ostale razvojne oblike nimf in odrasle samice, vendar le v omejenem obsegu. Pasiven prenos navadno poteka z vetrom, zemljo, vodo, pomemben dejavnik prenosa so živali in človek, predvsem s premikanjem rastlinskega materiala (Kosztarb in Kozar, 1988). 2.1 Družina Coccidae Klasifikacija družine Coccidae temelji večinoma na morfoloških lastnostih odraslih samic. Samice imajo enostavnejšo preobrazbo kot samci in preidejo tri ali štiri stadije, samci pa imajo pet razvojnih stadijev (Kosztarb in Kozar, 1988; Williams, 1997). Nimfe prve stopnje so eliptične oblike, navadno velike le od 0,3 do 1 mm, z dvema sestavljenima (facetnima) očesoma in štirimi dihalnimi odprtinami vzdolž telesa ter z dobro razvitimi nogami s krempeljcem na koncu petega člena. Tipalke so obdane s setami in imajo pet ali šest segmentov. Vsaka analna plošča je obdana z dolgimi apikalnimi setami. Analni obroč je obdan s šestimi setami. Spirakularne sete so najpogosteje nastale iz marginalnih. Večprekatnih por in tubularnih odprtin na trebušni strani nimajo (Kosztarb in Kozar, 1988; Williams, 1997). Samci in samice so si zelo podobni tudi na drugi razvojni stopnji, vendar tu že prihaja do razlikovanja oziroma do pojava dimorfizma, saj imajo samci na drugi tretjini telesa vzdolž hrbtne strani tubularne cevke, samice pa ne. Telo obeh spolov je pri tej razvojni stopnji navidezno razčlenjeno (segmentirano) s kožnimi gubami; imajo več set, cevk in por kot nimfe prvega stopnje (Williams, 1997). Telo je ovalno, pri samcih nekoliko bolj podolgovato. Analne plošče so brez dolgih apikalnih set. Tipalke in noge so zakrnele ali pa so dobro razvite. Samice so v tretjem razvojnem stadiju zelo podobne odraslim osebkom. Če jih ne opazujemo pod mikroskopom, jih lahko velikokrat spregledamo. Telo je ovalno, skoraj okroglo, z zelo dobro razvito analno režo. Tipalke so iz šestih ali sedmih delov ter iz od enega do treh parov set ali pa tipalk sploh nimajo. Lahko so brez nog ali pa so te dobro razvite. Hrbtne sete so ali niso prisotne, analne plošče z enim ali tremi pari šopov set pa so vedno navzoče. Na analnem obroču je navadno osem set, včasih samo šest. Nimfe tretjega razvojnega stadija imajo na splošno več por, set in ostalih kožnih struktur kot nimfe prejšnjega stadija, vendar manj kot odrasli osebki, tudi telo je manj segmentirano (Williams, 1997). Odrasle samice imajo še več set in por. Tubularne pore so največkrat prisotne, večprekatne pore so na trebušni strani telesa. Samci tretjega stadija, imenovanega tudi predbuba, se nahajajo v moknatem voščenem ovoju, ki ga oblikujejo na predhodni stopnji. V tej fazi se njihovo telo preobrazi v precej drugačno obliko od samičinega; nimajo analne plošče, oči, hrbtne pore, tubularnih cevk, niti set okoli dihalnih odprtin (Williams, 1997). Samci četrtega stadija, imenovanega tudi buba, so podobni prejšnjemu stadiju, z razliko, da so tipalke, spolni organi in noge že bolje oblikovani, še vedno pa nimajo oči. Noge in tipalke so dolge približno kot ena tretjina telesa, vidna je členjenost telesa. Telo odraslega samca je členjeno v tri regije. Na sklerotizirani glavi je od dva do pet parov enostavnih oči in par lateralnih ocelijev; ustnega aparata nimajo. Samci ostanejo v voskastem zapredku vse dokler niso popolnoma razviti. Zapredek nato poči, samci izletijo ter začnejo iskati samico. Oplojene samice so ovalne, navadno temno rjave barve, s konveksno, nagubano in močno sklerotizirano hrbtno stranjo. Otrdel eksoskelet mrtve samice služi kot zaščita jajčecem in novo izleglim nimfam (Kosztarb in Kozar, 1988). Predstavniki te družine se v Evropi razmnožujejo večinoma spolno, le pri nekaterih rodovih (npr. Parthenolecanium, Pulvinaria) poznamo tudi partenogenetsko razmnoževanje (Kosztarb in Kozar, 1988). Predstavniki iz družine Coccidae so večinoma univoltilni, se pravi, da imajo le en rod letno, z izjemo nekaterih vrst v območjih s toplejšim podnebjem, ki razvijejo od dva do tri rodove letno (npr. Parthenolecanium persicae in Parthenolecanium corni) (Kosztarb in Kozar, 1988). Življenjski krog je vrstno specifičen. Kaparji iz rodu Pulvinaria prezimijo kot odrasle samice, pri rodu Parthenolecanium predstavljajo prezimni stadij nimfe druge razvojne stopnje, medtem ko pri rodu Palaelecanium prezimijo jajčeca (Kosztarb in Kozar, 1988). Pri nas najdemo vrsto Palaelecanium bituberculatum Signoret na jablani (Malus domestica) in enovratem glogu (Crataegus monogyna) (Seljak, 2007). 2.1.1. Veliki trtni kapar (Neopulvinaria innumerabilis [Rathvon]) Veliki trtni kapar je eden izmed največjih in najbolj znanih kaparjev. V literaturi ga najdemo tudi pod imenom Pulvinaria innumerabilis (Koval in sod., 1996). Gre za polifagno žuželko nearktičnega izvora, ki je razširjena po vsej Ameriki in Kanadi (Pellizzari, 1997). V Evropi je razširjen na Hrvaškem (Masten in sod., 2007), v Rusiji, Franciji in Italiji (CABI, 2012), od koder je bil po vsej verjetnosti zanesen tudi v Slovenijo (Seljak, 1995; Seljak, 2007; Seljak, 2010). Pri nas so ga prvič našli leta 1985 na kakiju (Diospyros kaki), navadnem orehu (Juglans regia) in vinski trti (Vitis vinifera) (Seljak, 1995). Gospodarsko škodo so zabeležili le na vinski trti (Pellizzari, 1997), ki je zanj najpomembnejša gostiteljska rastlina (Seljak, 2007). Po trditvah Seljaka (2007) in Žežline (Seljak in Žežlina, 2007) je veliki trtni kapar pomemben škodljivec vinske trte, ki lahko pri nas povzroči občutno gospodarsko škodo. N. innumerabilis je univoltilna vrsta. Oplojena samica prezimi pretežno na enoletnem lesu (Seljak, 1995). V tem času je telo samice precej ploščato, dolgo okoli 5 mm (Koval in sod., 1996), rjave barve z ozkim grebenom vzdolž ščitka. Samice ostanejo spomladi prisesane na mestu prezimovanja, kjer začnejo pospešeno rasti (Seljak, 1995). Ščitek postane marmorirano rjavosiv in voščena obloga na hrbtu razpoka v pravokotne ploščice. Marginalne ščetine so povsem podobne stigmatalnim; so tope in krepke. Proti koncu maja začne samica izlegati jajčeca v jajčno vrečko (slika 1), ki je rahlo prečno nažlebičena, z osrednjo brazdo in voskastimi lepljivimi vlakni. V jajčni vrečki je okoli 3000 (Hadzibejli, 1955; Pellizzari, 1997), po nekaterih podatkih celo okoli 8700 jajčec (Conard, 1966), ki so bledo rožnate barve. Nimfe gredo skozi dve nimfalni stopnji. Slika 1: Samice N. innumerabilis z jajčno vrečko (foto: I. Mavrič Pleško) Picture 1: The adult females of N. innumerabilis with egg sac (photo: I. Mavrič Pleško) 2.1.2 Navadni trtni kapar (Pulvinaria vitis [L.]) Navadni trtni kapar je polifagna vrsta, najpogosteje pa se pojavlja na vinski trti. Napada liste, korenine in tudi stebla (Kosztarb in Kozar, 1988). Vrsta P. vitis jev Evropi splošno razširjena (Ben-Dov in sod., 2012), z gospodarskega stališča pa je precej nepomembna (Masten in sod., 2007). Samice navadnega trtnega kaparja so manjše od samic velikega trtnega kaparja. Dolge so od 2,5 do 6,5 mm, široke pa od 1,5 do 6,5 mm (Kosztarb in Kozar, 1988). Ščitek imajo enakomerno rjav, marginalne ščetine so tanjše in drugačne kot stigmatalne. Hrbtna stran ne razpoka kot pri velikem trtnem kaparju, temveč ostane cela. Jajčna vrečka nima prečnih žlebičev in vzdolžnega grebena, voskasta vlakna niso lepljiva. Jajčeca v njej so intenzivnejših barv, od oranžnorumene do bledo vinsko rdeče barve. Mlade samice prezimijo pretežno na dvoletnem, pa tudi starejšem lesu (Seljak, 1995), spomladi pa zelo hitro zrastejo do svoje končne velikosti. Jajčeca odlagajo od konca aprila do začetka junija. Samica v povprečju odloži okoli 3500 jajčec v jajčno vrečko, ki ima bombažni izgled in je nameščena pod ali za telesom samice. Proti koncu maja se začno izlegati mlade nimfe. Te se naselijo ob listne žile na spodnji strani lista. Razvoj navadnega trtnega kaparja poteka prek treh nimfalnih stopenj. V septembru (Pellizzari, 1997) in oktobru (Kosztarb in Kozar, 1988) se odrasle samice parijo in se nato ob koncu oktobra preselijo na veje, kjer prezimijo (Pellizzari, 1997). Vrsta P. vitis je univoltilna. Schumutterer (1952) navaja, da se v Evropi navadno razmnožuje spolno, znano pa je, da se lahko razmnožuje tudi partenogenetsko. V Severni Ameriki se razmnožuje le partenogenetsko (Phillips, 1963; Grill, 1988; Kosztarb in Kozar, 1988). 2.1.3 Češpljev kapar (Parthenolecanium corni [Bouché]) Češpljev kapar ima več poimenovanj, med katerimi sta najpogostejša Eulecanium corni Bouché (Janežič, 1954; Hamon, 1984; Kosztarb in Kozar, 1988;) in Lecanium corni Bouché (Hamon, 1984; Kosztarb in Kozar, 1988;). Kapar P. corni je kozmopolitska in polivoltilna vrsta. Letno ima od enega do treh rodov, v razvoju pa se pojavljata dve nimfalni stopnji (Pellizzari, 1997). Število rodov je odvisno od podnebja in gostiteljskih rastlin. Na severu Madžarske so zabeležili en rod, na jugu pa dva rodova na leto. O treh rodovih so poročali iz Kavkaza in iz Srednje Azije (Kosztarb in Kozar, 1988). Oblika, velikost in obarvanost odraslih samic je odvisna od njihove starosti in gostiteljskih rastlin, na katerih se prehranjujejo. Popolnoma odrasle so dolge okoli šest in široke okoli štiri mm. So rjave barve, hrbtna stran telesa pa je precej konveksna in močno sklerotizirana. Vrsta P. corni prezimi v drugi stopnji nimfe. Proti koncu maja se razvijejo odrasli osebki in oplojene samice začnejo odlagati jajčeca. Nov zarod kaparjev se razvije v drugi polovici junija. Mlade nimfe se prehranjujejo na spodnji strani listov, po prehodu v drugo stopnjo pa se preselijo na lesnate dele. O masovnih izbruhih vrste P. corni so poročali iz Evrope po letu 1880, pojavljala pa se je v od deset - do enajstletnih intervalih. Od zadnjega masovnega pojava te vrste leta 1955 je njena številčnost močno upadla, predvidoma zaradi parazitiranja vrste Blastotrix confusa Erdos. Večji izbruh je bil nato ugotovljen še leta 1975, vendar v precej manjšem obsegu kot v preteklosti (Kosztarb in Kozar, 1988). V Evropi je češpljev kapar splošno razširjen (Ben-Dov in sod., 2012), v Sloveniji pa je bil prvič najden leta 1954 (Janežič, 1954). 2.2 Družina Pseudococcidae Družina Pseudococcidae je zelo raznolika. Telo samice je navadno ovalne oblike, sestavljeno je iz deset segmentov (McKenzie, 1967) in je sive, rožnate ali najpogosteje rumenkaste barve, odvisno od vrste. Tipalke so sestavljene iz dveh do devetih segmentov, oči so kupolaste ali manjkajo. Za razliko od predstavnikov družine Coccidae sta pri tej družini prisotna le dva para dihalnih odprtin. Za predstavnike družine Pseudococcidae so značilni cerariji, strukture nameščene ob robu, vzdolž hrbtne strani telesa. Sestavljene so iz por in set, včasih tudi sklerotizirane (Kosztarb in Kozar, 1988). Odrasle samice družine Pseudococcidae prepoznamo po vulvi, ki jo najdemo na trebušni strani med osmim in devetim telesnim segmentom (Kosztarb in Kozar, 1988). Samice izločajo na hrbtni strani voščeni poprh, s katerim se zaščitijo, jajčeca pa izlegajo v jajčno vrečko iz voščenih niti, ki so podobne barve kot samica. Jajčeca so ovalna, rumenkasta, dolga okoli 0,5 mm in široka med 0,2 in 0,3 mm. Novo izlegle nimfe so na prvi pogled zelo podobne jajčecem, le da imajo dobro razvite dolge noge, šestčlenaste tipalke in majhne oči. Nimfe ne izločajo voščenega poprha, spola se na tej razvojni stopnji ne da določiti. Nimfe samic druge razvojne stopnje so podobne prvi, od katere se razlikujejo po nekaj razvitih tubularnih cevkah na obeh straneh telesa in odprtini na zadnjem koncu hrbtne strani, ki je zastopana pri večini primerkov (slika 2). Slika 2: Ličinke kaparjev iz družine Pseudococcidae različnih razvojnih stopenj (foto: I. Mavrič Pleško) Picture 2: The immature stages of Pseudococcidae (photo: I. Mavrič Pleško) Samci druge razvojne stopnje so podobni samicam, a imajo več cevk in razvit dodaten člen na tipalkah. Nimfe tretje razvojne stopnje samic imajo razvitih več por in cevk kot mlajše stopnje, odprtina na zadnjem delu je razvita, prav tako tudi dodaten segment na tipalkah, vendar eden manj kot pri odraslih osebkih. Pri tretji nimfalni stopnji samcev ali t.i. predbubi se noge in tipalke zmanjšajo. Imajo le še nekaj kratkih set in kratke zasnove kril. Naslednji stadij pri samcih je buba, pri kateri se podaljšajo osnove kril, deseti segment telesa sklerotizira, delno otrdi tudi predel glave in trupa. Telo odraslega samca je podolgovato vretenasto. Navadno ima dobro razvit par kril na mezotoraksu, dva para enostavnih oči in par lateralnih ocelijev. Tipalke in noge so dolge s številnimi setami. Znane so najmanj štiri oblike odraslih samcev: krilati, nekrilati, z reduciranimi krili ali s telesom, ki spominja na nimfo (Kosztarb in Kozar, 1988). Samica proti koncu maja in v začetku junija izleže v jajčno vrečko več kot 1800 jajčec. Iz teh se v treh do šestnajstih dneh razvijejo nimfe. Sprva se aktivno premikajo in iščejo najustreznejše mesto za prehranjevanje. Nimfe se v drugi razvojni stopnji večinoma vrnejo v razpoke na veje in debla gostiteljskih rastlin na prezimovanje, kjer so zbrane v majhnih voščenih kokonih (Kosztarb in Kozar, 1988). V času prezimovanja lahko preidejo v stadij mirovanja jajčeca, mlade nimfe in odrasle samice (Miller, 2005). Spomladi se nimfe in odrasle samice hranijo na deblih in vejah (Kosztarb in Kozar, 1988). Evropske vrste teh kaparjev imajo na prostem navadno od enega do tri rodove na leto, v zavarovanih prostorih pa celo od šest do osem. Tudi nekatere vrste te družine se lahko razmnožujejo partenogenetsko (McKenzie, 1967; Kosztarb in Kozar, 1988). Večina kaparjev družine Pseudococcidae, ki živijo na vinski trti, tudi vrsta Planococcus ficus, lahko sklene razvojni krog v celoti na tej gostiteljski rastlini (Walton in Pringle, 2004b). 2.2.1 Smokvin volnati kapar (Planococcus ficus [Signoret]) Telo vrste P. ficus je svetlo rožnate do svetlo sive barve, pokrito z voščenim poprhom, ki postane med razvojem bolj viden. Odrasle samice so ovalne, dolge približno štiri in široke malo več kot dva mm (Walton in Pringle, 2004b). Tipalke imajo sestavljene iz osmih segmentov. So brez kril. Za razliko od samic so samci krilati, s tremi pari lateralnih ocelijev ter dolgimi filamentoznimi analnimi setami (Kreiger, 1954 povz. po Walton in Pringle, 2004b) (slika 3). Slika 3: Smokvin volnati kapar, odrasla samica (levo) in samec (desno) (foto: M. Štrukelj) Picture 3: The vine mealybug, adult female (left) and male (right) (photo: M. Štrukelj) Seljak (2007) je smokvinega volnatega kaparja našel leta 2000 na vinski trti (Vitis vinifera) in gumovcu (Ficus elastica). Zaradi podobnosti lahko to vrsto zamenjamo s citrusovim kaparjem (Planococcus citri [Risso]), in vrstama Planococcus minor (Maskell) in Planococcus halli Ezzat & McConnell (Miller in sod., 2007). Te vrste nimajo enakih gostiteljskih rastlin. Vrsto P. ficus, kot že prej omenjeno, najpogosteje najdemo na vinski trti, medtem ko je vrsta P. halli pogosta na krompirju, vrsta P. minor pa je precej polifagna (Miller in sod., 2007). 3 ŠKODLJIVOST IN NAČINI ZATIRANJA KAPARJEV Kaparji so pomembni škodljivci vinske trte, ki so s sesanjem rastlinskega soka neposredno škodljivi in lahko povsem izčrpajo rastline. Oslabljene rastline so dovzetnejše za napade drugih škodljivcev in okužbe s patogenimi organizmi. Posredna škoda nastaja zaradi izločanja medene rose, na katero se naselijo glive sajavosti, ki zmanjšujejo fotosintezo ter vplivajo na razvoj in tržno vrednost rastlin in pridelka. Kaparji predstavljajo precejšen problem pri pridelavi grozdja, zato jih je potrebno zatirati bodisi z uporabo insekticidov ali z okolju prijaznejšimi načini varstva rastlin. Preden se lotimo njihovega zatiranja moramo dodobra spoznati njihovo bionomijo. Za insekticide so najbolj občutljivi v začetku razvoja, ko so nimfe še popolnoma brez zaščite oziroma voščenega poprha. Navadno so nimfe skrite na spodnji strani listov, pod lubjem in v razpokah, kar otežuje njihovo zatiranje. Kolonije odraslih kaparjev družine Pseudococcidae so zavarovane z voščenim poprhom, predstavniki družine Coccidae pa s ščitkom, kar zmanjšuje učinkovitost insekticidov. Prvi poskusi kemičnega zatiranja velikega trtnega kaparja so bili v Sloveniji opravljeni v začetku devetdesetih let (Seljak, 1995). Zadovoljivo delovanje proti omenjenemu škodljivcu so dosegli s pripravkoma z aktivno snovjo diazinon (Seljak in Žežlina, 2007), ki pa v Sloveniji ni več na seznamu dovoljenih sredstev (Registrirana..., 2012). Za zatiranje kaparjev so trenutno v Sloveniji registrirani pripravki na podlagi abamektina, acetamiprida, dimetoata, olja navadne ogrščice, parafinskega olja, piretrina, tiakloprida in tiametoksama (Registrirana., 2012), vendar njihova učinkovitost pri zatiranju kaparjev še ni bila preučena (Seljak in Žežlina, 2007). Uporaba insekticidov negativno vpliva na naravne sovražnike. Z nepravilno in prepogosto rabo fitofarmacevtskih sredstev lahko povzročimo tudi pojav odpornosti kaparjev, zato moramo večjo pozornost nameniti okoljsko sprejemljivejšim načinom zatiranja teh škodljivcev, na primer mehanskemu in biotičnemu načinu zatiranja. Mehanskih načinov se poslužujemo takrat, ko škodljivcev na rastlini ni veliko. Odstranimo jih lahko s krtačo ali s spiranjem s toplo vodo (Kosztarb in Kozar, 1988), dovolj učinkovito je tudi odstranjevanje kaparjev z rokavico ali krpo (Seljak in Žežlina, 2007). To pri predstavnikih družine Coccidae navadno napravimo v maju in v začetku junija, ko imajo samice razvito jajčno vrečko in se nimfe še niso izlegle (Seljak in Žežlina, 2007). V kolikor je populacija kaparjev na rastlinah številčnejša, je kemično zatiranje neizogibno. Med okoljsko sprejemljive načine zatiranja štejemo tudi setev varovalnih posevkov (angl. cover crops) v vrste med glavne posevke. Namen teh posevkov je povečanje populacije koristnih organizmov in bolj raznolik ekosistem, saj organizmom zagotavlja več hrane in prostora (Trdan in sod., 2006; Laznik in sod., 2012). Ti posevki so bili v vinogradih učinkoviti le, če so privabili polonice (Coccinellidae) in mrežekrilce (Neuroptera) (Bugg in Wassington, 1994). Costello in Daane (1996) pa z raziskavami nakazujeta, da varovalni posevki nimajo bistvenega vpliva na pojavljanje naravnih sovražnikov smokvinega volnatega kaparja v vinogradih. 3.1 Naravni sovražniki Glavni cilj biotičnega varstva rastlin je oblikovanje naravnega ravnovesja med škodljivci in njihovimi naravnimi sovražniki ter s tem preprečitev močnejše namnožitve škodljivcev (Vrabl, 1990). Biotično varstvo rastlin vključuje plenilce in parazitoide, ki so naravni sovražniki kaparjev (preglednice 1-4) in lahko znatno zmanjšajo njihovo populacijo. Naravni sovražniki so navadno škodljivi le nimfam, občasno tudi jajčecem, ptice pa se hranijo tudi z odraslimi kaparji in njihovimi jajčeci. V Sloveniji biotično zatiranje kaparjev še ni dobro raziskano, čeprav se je biotično varstvo nekaterih kaparjev v srednji Evropi izkazalo za uspešno (Kosztarb in Kozar, 1988). Največ tovrstnih raziskav je bilo doslej narejenih v Južni Afriki (Walton in Pringle, 2004ab), Ameriki (Triapitsyn in sod., 2006) ter v Argentini in Iranu (Walton in Pringle, 2004ab). Walton in Pringle (2004b) trdita, da imajo plenilci pomembnejšo vlogo v biotičnem varstvu vinske trte kot parazitoidi. V splošnem so polonice (Coccinellidae) najpomembnejši plenilci kaparjev. Med parazitoidi prevladujejo parazitske osice iz družin Aphelinidae in Encyrtidae (preglednice 1-4). Preglednica 1: Naravni sovražniki velikega trtnega kaparja (N. innumerabilis) (Pellizzari, 1997; Seljak in Žežlina, 2007) Table 1: Natural enemies of cottony maple scale (N. innumerabilis) (Pellizzari, 1997; Seljak in Žežlina, 2007) Red in družina Vrsta Coleoptera: Anthribidae Brachytarsus nebulosus Foster Coleoptera: Coccinellidae Exochomus quadripustulatus L. Hyperaspis signata Olivier Hymenoptera: Aphelinidae Coccophagus lycimnia Walker Encarsia lutea Masi Hymenoptera: Chalciodoidea Blastothrix britannica Girault Blastothrix hungaricus Erdos Hymenoptera: Encyrtidae Metaphycus dispar Mereet Metaphycus insidiosus Mercet Metaphycus punctipes Dalman Preglednica 2: Naravni sovražniki malega trtnega kaparja (P. vitis) (Kosztarb in Kozar, 1988; Pellizzari, 1997) Table 2: Natural enemies of cottony grape scale (P. vitis) (Kosztarb in Kozar, 1988; Pellizzari, 1997) Red in družina Vrsta Coleoptera: Anthribidae Brachytarsus nebulosus Föster Coleoptera: Coccinellidae Vrste iz rodu Scymnus Diptera: Chamacmyiidae Leucopis (Leucopomya) silesiaca Egger Leucopis annilipes Zetterstedt Leucopis nigricornis Egger Hymenoptera: Aphelinidae Coccophagus gigas Eldos Coccophagus insidiator Dalman Coccophagus lycimnia Walker Coccophagus scutellaris Dalman Hymenoptera: Encyrtidae Cheilonerus formosus Boheman Encyrtus albitarsus Zetterstedt Metaphycus dispar Mercet Metaphycus insidiosus Mercet Metaphycus punctipes Dalman Microterys duplicatus Nees Neuroptera: Chrysopidae Chrysoperla carnea Stephen Preglednica 3: Naravni sovražniki češpljevega kaparja (P. corni) (Kosztarb in Kozar, 1988; Pellizzari, 1997) Table 3: Natural enemies of brown scale (P. corni) (Kosztarb in Kozar, 1988; Pellizzari, 1997) Red in družina Vrsta Coleoptera: Coccinellidae Adalia bipunctata L. Chilocorus bipustulatus L. Coccinella septempunctata L. Exochomus quadripustulatus L. Hymenoptera: Aphelinidae Coccophagus lycimnia Walker Coccophagus scutellaris Dalman Hymenoptera: Chalciodoidea Blastothrix confusa Erdös Hymenoptera: Encyrtidae Metaphycus insidiosus Mercet Microterys sylvius Dalman Trichomasthus albimanus Thomson Neuroptera: Chrysopidae Chrysopa perla L. Preglednica 4: Naravni sovražniki smokvinega volnatega kaparja (P. ficus) (Mgocheki in Addison, 2009; Triapitsyn in sod., 2007; Walton in Pringle, 2004ab) Table 4: Natural enemies of vine mealybug (P. ficus) (Mgocheki in Addison, 2009; Triapitsyn in sod., 2007; Walton in Pringle, 2004ab) Red in družina Vrsta Coleoptera: Coccinellidae Diptera: Chamamelyidae Hymenoptera: Encyrtidae Hymenoptera: Pteromalidae Hymenoptera: Signiphoridae Neuroptera: Chrysopidae Cryptolaemus montrouzieri Mulsant Cydonia lunata F. Hippodamia sp. Hyperaspis felixi Mulsant Nephus angustus Casey Nephus binaevatus Mulsant Nephus quadrivittatus Mulsant Nephus reunioni Fürsch Rhizobiellus sp. Scymnus nubilis Mulsant Leucipis sp. Allotropa mecrida Walker Angyrus pseudococci Girault Chartocerus subaeneus Förster Cheilonerus spp. Chrysoplatycerus splenders Howard Clausenia josefi Rosen Coccidoxenoides perminutus Timberlake Lapmastidea abnormis Girault Laptomastix dactylopii Howard Laptomastix flavus Mercet Prochiloneurus pulchellus Silvestri Pachyneuron concolor Förster Pachyneuron sp. Chartocerus spp. Chrysoperla carnea Stephen_ V Južni Afriki so raziskovalci v dvoletnem poljskem poskusu uporabili parazita Coccidoxenoides perminutus za zatiranje vseh razvojnih stopnej ličink vrste P. ficus. Walton in Pringle (2004b) poročata, da je bil tak način zatiranja vsaj tako učinkovit kot zatiranje škodljivca z uporabo insekticidov. Po podatkih Seljaka in Žežline (2007) sta pri nas naravna sovražnika velikega trtnega kaparja polonica Exochomus quadripustulatus in osica Coccophagus lycimnia. Ostali plenilci kaparjev pa v Sloveniji za enkrat še niso preučeni. Učinkovitost naravnih sovražnikov zmanjšujejo mravlje z branjenjem kaparjev (Buckley in Gullan, 1991; Mgocheki in Addison, 2009). Kaparji z izločanjem medene rose oskrbujejo mravlje s hrano, slednje pa jih zato branijo ter hkrati preprečujejo odlaganje jajčec parazitskih organizmov v telesa kaparjev. 4 ZAKLJUČKI S pospešeno globalizacijo trgovanja z rastlinami se povečuje vnos žuželk in drugih organizmov v njim tujerodno okolje. Kaparji predstavljajo kar 41,1 % (37 vrst) vseh polkrilcev (Hemiptera), ki so bili v zadnjih 20 letih vneseni ali pa so se postopno razširili v Slovenijo (Seljak, 2011). Škodljivi so predvsem na sadnem drevju, vinski trti, grmičevju in rastlinah v zavarovanih prostorih (Kosztarb in Kozar, 1988). Seljak in Žežlina (2007) izpostavljata štiri vrste kaparjev, ki lahko v Sloveniji povzročajo gospodarsko škodo na vinski trti; velikega trtnega kaparja, navadnega trtnega kaparja, češpljevega kaparja in smokvinega volnatega kaparja. Kaparji se hranijo z rastlinskimi sokovi in povzročajo postopno propadanje rastlin. Na svoje gostitelje ne vplivajo le neposredno, s sesanjem, vendar tudi posredno, s prenosom virusov vinske trte ter izločanjem medene rose, na katero se lahko naselijo glive sajavosti, ki lahko povzročijo precejšnjo gospodarsko škodo. Kaparje lahko zatiramo z insekticidi in mehanskimi ukrepi, vse bolj pa prihaja v ospredje zavedanje o pomenu biotičnega varstva vinske trte. Insekticidi, ki so jih v Sloveniji proti velikemu trtnemu kaparju precej učinkovito uporabljali pred nekaj leti, danes niso več na seznamu dovoljenih sredstev. Na splošno so insekticidi najbolj učinkoviti proti na novo izleglim nimfam kaparjev, ki niso zaščitene z voščenim poprhom, kot na primer odrasle samice. Biotično varstvo vinske trte temelji na uporabi plenilcev in parazitoidov, ki so naravni sovražniki kaparjev in lahko precej zmanjšajo njihovo populacijsko gostoto. Po nekaterih navedbah naj bi imeli plenilci, zlasti polonice (Coccinellidae), pri zatiranju kaparjev večji pomen od parazitoidov (predstavnikov družin Aphelinidae in Encyrtidae). Pri uvajanju biotičnega varstva rastlin, ki temelji na uporabi vrst, ki v našem okolju naravno niso zastopane (klasično biotično varstvo), oziroma na uporabi tako imenovanih tujerodnih generalistov, pa moramo biti izjemno previdni, da ne povzročimo okolju več škode kot koristi. 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World Crop Pests, Soft Scale Insects their Biology, Natural Enemies and Control, 7(A): 31-48 CONTENT ANALYSIS OF THE PAPERS IN THE ACTA AGRICULTURAE SLOVENICA VSEBINSKA OBDELAVA PRISPEVKOV V ACTA AGRICULTURAE SLOVENICA let. 99 št. 2 Tomaž BARTOLa, Karmen STOPARb, SUBJECT INDEX BY AGRIS CATEGORY CODES VSEBINSKO KAZALO PO SKUPINAH ZNANJA (PREDMETNIH KATEGORIJAH) A01 Kmetijstvo splošno 175-183 C20 Kmetijsko svetovanje 175-183 C30 Dokumentacija in informatika 175-183 E16 Ekonomika proizvodnje 137-142 E20 Organizacija kmetij 191-199 E51 Kmečko prebivalstvo 191-199 F01 Agronomija, rastlinska proizvodnja 121-128, 137-142, 191-199 F06 Namakanje 235-253 F30 Rastlinska genetika in žlahtnjenje rastlin 121-128, 143-150 f60 Fiziologija rastlin in biokemija 129-136 F62 Fiziologija rasti in razvoja 129-136, 185-189 F70 Taksonomija rastlin, geografija rastlin 143-150 H10 Škodljivci rastlin 213-223, 225-234, 255-269 H20 Bolezni rastlin 151-164, 255-269 N20 Kmetijska mehanizacija in oprema 151-164 P10 Vodni viri in vodno gospodarstvo 165-173, 235-253 S20 Fiziologija prehrane ljudi 201-211 S30 Hrana in alimentarne bolezni 201-211 SUBJECT INDEX BY AGROVOC DESCRIPTORS PREDMETNO KAZALO PO DESKRIPTORJIH AGROVOC adaptation 129-136 adult education 175-183 advisory officers 175-183 agriculture 175-183 agronomic characters 121-128 allergens 225-234 application methods 151-164 a Assoc. Prof., Ph. D., M. Sc.., B. Sc., Jamnikarjeva 101, SI-1000 Ljubljana, P. O. Box 95 b B.Sc., M.Sc., ibid appropriate technology 175-183 beneficial organisms 225-234 biological control 225-234, 255-269 biological control organisms 225-234 biological development 129-136 biological differences 121-128 biosystematics 255-269 callus 185-189 cereal crops 235-253 cereals 121-128, 137-142 chemical control 151-164 chemicophysical properties 201-211 cherries 129-136 citrus sinensis 185-189 climatic change 235-253 climatic factors 129-136 coccidae 255-269 communication technology 175-183 control methods 151-164, 255-269 crop management 191-199 crop yield 121-128, 255-269 cultivation 191-199 culture media 185-189 damage 225-234, 255-269 data collection 175-183, 191-199, 213-223, 235-253 data processing 175-183 designation of origin 143-150 developing countries 175-183 development indicators 191-199 dietary fibres 201-211 disease control 151-164, 201-211 disease transmission 255-269 drought 235-253 ecology 225-234, 255-269 education 175-183 efficiency 137-142 embryonic development 185-189 energy consumption 137-142 energy value 137-142 equipment 151-164, 165-173 evapotranspiration 165-173 extension activities 175-183 farm surveys 191-199 farmers 191-199 fertilizers 137-142 flowering 129-136 fruit 185-189 fruit crops 129-136, 185-189 fruit growing 129-136 fruit vegetables 191-199 fruits 129-136 fungicides 151-164 genetic distance 143-150 genetic markers 143-150 genetic parameters 143-150 genetic variation 121-128, 143-150 genotypes 121-128, 143-150 grapevines 143-150, 213-223, 255-269 groundwater 165-173 groundwater pollution 165-173 growing media 185-189 growth 129-136 harmonia axyridis 225-234 health 201-211 hosts 255-269 human nutrition 201-211 hypersensitivity 225-234 identification 225-234 information processing 175-183 information services 175-183 information systems 175-183 information technology 175-183 input output analysis 137-142 insect control 255-269 insecticides 255-269 irrigation 235-253 land ownership 191-199 land varieties 121-128, 129-136, 137-142, 143-150 lycopersicon esculentum 191-199 lysimeters 165-173 maize 121-128, 137-142, 235-253 mankind 201-211 maturation 185-189 measuring instruments 165-173 meteorological instruments 165-173 microsatellites 143-150 models 235-253 monitoring 213-223,235-253 natural enemies 225-234 nitrogen fertilizers 137-142 nozzles 151-164 nucleus 185-189 nutrition physiology 201-211 oils 121-128 orchards 129-136 ownership 191-199 pest control 225-234, 255-269 pest control equipment 213-223 pest insects 213-223, 255-269 pest surveys 213-223 phenotypes 121-128 physiological functions 201-211 plant breeding 121-128, 129-136 plant cover 165-173 plant developmental stages 129-136, 185-189 plant embryos 185-189 plant growth substances 185-189 plant nurseries 213-223 plant production 137-142, 191-199 plant protection 151-164 plant protection equipment 151-164 plant water relations 235-253 polymorphism 143-150 postharvest losses 191-199 potatoes 151-164 precipitation 165-173 precipitation deficit 235-253 productivity 137-142 proteins 121-128 proximate composition 121-128, 129-136 prunus avium 129-136 quality 121-128, 129-136 quality controls 143-150 regeneration 185-189 resource management 165-173 root vegetables 151-164 rootstocks 129-136 rural population 191-199 scaphoideus titanus 213-223 seed 121-128 seedlings 185-189 social change 175-183 socioeconomic development 175-183 soil water retention 235-253 solanum tuberosum 151-164 sprayers 151-164 standardizing 143-150 starch 121-128 stone fruits 129-136 surveys 191-199, 213-223 sweet oranges 185-189 taxonomy 255-269 temperature 235-253 therapeutic diets 201-211 thermal stress 235-253 tomatoes 191-199 traps 213-223 urban environment 225-234 varieties 121-128, 129-136, 143-150, 191-199 vectors 255-269 vegetative period 235-253 vineyards 213-223, 255-269 vitis vinifera 143-150, 213-223, 255-269 water balance 165-173, 235-253 water management 165-173 water pollution 165-173 water requirements 235-253 water resources 165-173 water use 165-173 weather data 235-253 weather hazards 235-253 yields 121-128 zea mays 121-128, 137-142, 235-253 POPRAVEK/CORRIGENDUM Za zvezek 99-1 pravilna slika v članku Selenium supplementation stimulates vegetative and reproductive growth in canola (Brassica napus L.) plants (na strani 16). In issue 99-1 correct picture in article Selenium supplementation stimulates vegetative and reproductive growth in canola (Brassica napus L.) plants (on page 16). Figure 1: Effect of Se supplementation on the number of leaves (a) and length of stem (b) in canola (Brassica napus) plants grown in greenhouse NAVODILA AVTORJEM (letniki z liho številko - rastlinska proizvodnja) Prispevki Sprejemamo izvirne znanstvene članke s področja agronomije, hortikulture, rastlinske biotehnologije, raziskave živil rastlinskega izvora, agrarne ekonomike in informatike ter s sorodnih področij - letniki z liho številko (npr. 97, 99) - v slovenskem in angleškem jeziku; pregledne znanstvene članke samo po poprejšnjem dogovoru. Objavljamo tudi izbrane razširjene znanstvene prispevke s posvetovanj, vendar morajo taki prispevki zajeti najmanj 30 % dodatnih originalnih vsebin, ki še niso bile objavljene. O tovrstni predhodni objavi mora avtor obvestiti uredniški odbor. Če je prispevek del diplomske naloge, magistrskega ali doktorskega dela, navedemo to in tudi mentorja na dnu prve strani. Navedbe morajo biti v slovenskem in angleškem jeziku. Prispevke sprejemamo vse leto. Podrobnejša navodila: http://aas.bf.uni-lj.si/navodila.htm INSTRUCTIONS FOR AUTHORS (Odd-numbered volumes - plant production) Articles The Journal accepts original scientific articles from the fields of agronomy, horticulture, plant biotechnology, plant-related food-and-nutrition research, agricultural economics, information-science, and related research - odd-numbered volumes (for example: 97, 99) -in Slovenian or English language. Review articles are published in advance agreement with the editorial board. Extended versions of selected proceedings-papers can also be considered for acceptance, provided they include at least 30% of new original content, but the editorial board must be notified beforehand. If the article is based on a thesis or dissertation, the thesis-type must be indicated (BSc, MSc, PhD...), along with the role of the candidate and advisor, at the bottom of the first article page. Manuscripts are accepted throughout the year. Detailed instructions: http: //aas. bf. uni -lj. si/instructi ons. htm